Achondroplasia is characterized by
abnormal bone growth that results in short stature with disproportionately
short arms and legs, a large head, and characteristic facial
features with frontal bossing and mid-face hypoplasia. In
infancy, hypotonia is typical, and acquisition of developmental
motor milestones is often delayed. Intelligence and life span
are usually normal, although compression of the spinal cord
and/or upper airway obstruction increases the risk of death
in infancy.
Albinism-OCA 1 Tyrosinase
gene sequencing/ Albinism-OCA 2 gene-Common deletion
Oculocutaneous albinism (OCA) is caused by reduced or deficient
melanin pigmentation in the skin, hair, and eyes. OCA has
different phenotypes resulting from mutations in distinct
pigmentation genes involved in melanogenesis. OCA type 2 (OCA2),
the most common form of OCA, is an autosomal recessive disorder
caused by mutations in the P gene.
Alkaptonuria-linkage studies/ Prenatal Diagnosis-linkage
Alkaptonuria is an inherited condition that causes urine to
turn black when exposed to air. Ochronosis, a buildup of dark
pigment in connective tissues such as cartilage and skin,
is also characteristic of the disorder. This blue-black pigmentation
usually appears after age 30. People with alkaptonuria typically
develop arthritis, particularly in the spine and large joints,
beginning in early adulthood. Other features of this condition
can include heart problems, kidney stones, and prostate stones.
Alpha 1 Anti
Typsin (Z, S & M Mutation)
Alpha 1 Antitrypsin (A1AT) is a serine protease inhibitor
required for the prevention of proteolytic tissue damage,
principally in the lung, by neutrophil elastase released by
inflammatory cells. While severe A1AT deficiency is the major
factor leading to emphysema and related pulmonary diseases,
it is also associated with neonatal hepatitis and cirrhosis.
Alpha thalassemia-deletions
Alpha thalassemia occurs when one or more of the four alpha
chain genes fails to function. The loss of one gene diminishes
the production of the alpha protein only slightly. This condition
is very close to normal and is called a "silent carrier"
because of the difficulty in detection. The loss of two genes
(two-gene deletion alpha thalassemia) produces a condition
with small red blood cells, and at most a mild anemia. People
with this condition look and feel normal. The loss of three
alpha genes produces a serious hematological problem (three-gene
deletion alpha thalassemia). Patients with this condition
have a severe anemia, and often require blood transfusions
to survive. The loss of all four alpha genes produces a condition
that is incompatible with life. Most people with four-gene
deletion alpha thalassemia die in utero or shortly after birth.
Aneuploidy screening
(21, 18, 13, X, Y, chm)
Aneuploidy is most often a result of incorrect division of
chromosomes in the eggs of ageing women. Females, at birth,
have their entire allotment of eggs, and as they age, their
eggs age as well. When the eggs are finally recruited from
a resting stage before ovulation, their chromosomes must undergo
a certain number of divisions before fertilization occurs.
It is during these divisions that errors may occur, and can
affect the development and viability of the fertilized egg
or embryo.
Aneuploidy screening avoids the transfer of embryos that would
never implant due to chromosome abnormalities; thus maximizing
your chances of getting pregnant in a single cycle. Additionally,
studies have shown that PGD for aneuploidy increases implantation
rates, reduces the rate of pregnancy loss by half, and increases
take-home baby rates. Angelman
Syndrome (methylation test)
The severity of the symptoms associated with AS varies significantly
across the population of affected persons. Some speech and
a greater degree of self-care are possible among the least
profoundly affected. Unfortunately, walking and the use of
simple sign language may be beyond the reach of the more profoundly
affected. As adulthood approaches, hyperactivity and poor
sleep patterns improve. Apert
Syndrome
Apert Syndrome is a genetic defect and falls under the broad
classification of craniofacial/limb anomalies. The major symptoms
are prematurely fused cranial sutures, A retruded midface
,Fused fingers, Fused toes. Apo
E Genotyping
This test is done to identify the conditions like; evaluation
of a possible genetic component to atherosclerosis, help treating
decisions for individuals with cardiovascular disease, as
an aid in the diagnosis of probable late onset Alzheimer's
disease in a symptomatic adult, or to help confirm a diagnosis
of Type III hyperlipoproteinemia (also known as familial dysbetalipoproteinemia)
Ataxia Telangiectasia-carrier
screening by linkage
Ataxia telangiectasia (AT) is an autosomal recessive, multi-system
disorder characterized by progressive neuromuscular and vascular
degeneration. AT patients exhibit cerebellar ataxia; oculocutaneous
telangiectases; and various immune defects including underdevelopment
of the thymus leading to recurrent sinopulmonary infections.
Its most unusual symptom is an acute sensitivity to ionizing
radiation, such as X-rays or gamma-rays. The first signs of
the disease, which include delayed development of motor skills,
poor balance, and slurred speech, usually occur during the
first decade of life. Telangiectasias (tiny, red "spider"
veins), which appear in the corners of the eyes or on the
surface of the ears and cheeks, are characteristic of the
disease, but are not always present and generally do not appear
in the first years of life. About 20% of those with A-T develop
cancer, most frequently acute lymphocytic leukemia or lymphoma.
Many individuals with A-T have a weakened immune system, making
them susceptible to recurrent respiratory infections. Other
features of the disease may include mild diabetes mellitus,
premature graying of the hair, difficulty swallowing, and
delayed physical and sexual development. Children with A-T
usually have normal or above normal intelligence.
Ataxia Telangiectasia-PND
by linkage
Ataxia telangiectasia (AT) is an autosomal recessive, multi-system
disorder characterized by progressive neuromuscular and vascular
degeneration. AT patients exhibit cerebellar ataxia; oculocutaneous
telangiectases; and various immune defects including underdevelopment
of the thymus leading to recurrent sinopulmonary infections.
Canavan Disease-
Asparto asylase (ASPA) gene sequencing
Mutations in the gene for aspartoacylase (ASPA), which catalyzes
deacetylation of N-acetyl-Laspartate in the central nervous
system (CNS), result in Canavan Disease, a fatal dysmyelinating
disease. Canavan Disease (CD) is a neurodegenerative disorder
most prevalent among Ashkenazi Jews. The pathology of CD is
marked by brain vacuolization and dysmyelination, resulting
in death during childhood. Charcot
Marie Tooth disease 1/ HNPP (Del/Dupl. PMP gene)
Charcot Marie Tooth disease is a heterogeneous inherited disorder
of nerves (neuropathy) that is characterized by loss of muscle
tissue and touch sensation, predominantly in the feet and
legs but also in the hands and arms in the advanced stages
of disease. Presently incurable, this disease is one of the
most common inherited neurological disorders, with 37 in 100,000
affected. CMV-Cytomegalovirus-PCR
A virus that infects 50-85% of adults in the US by age 40
and is also the virus most frequently transmitted to a child
before birth. Persons with symptoms have a mononucleosis-like
syndrome with prolonged fever and mild hepatitis. Once a person
becomes infected, the virus remains alive and usually dormant
within that person's body for life. Recurrent disease rarely
occurs unless the person's immune system is suppressed due
to therapeutic drugs or disease. CMV infection is therefore
a concern because of the risk of infection to the unborn baby,
people who work with children, and immunodeficient people
such as transplant recipients and those with HIV.
Congenital Adrenal Hyperplasia-Common
deletion
Congenital adrenal hyperplasia (CAH) refers to any of several
autosomal recessive diseases resulting from mutations of genes
for enzymes mediating the biochemical steps of production
of cortisol from cholesterol by the adrenal glands (steroidogenesis).
Most of these conditions involve excessive or deficient production
of sex steroids and can alter development of primary or secondary
sex characteristics in some affected infants, children, or
adults. Examples of conditions caused by various forms of
CAH: • ambiguous genitalia, in some females,
such that it can be initially difficult to determine sex
• vomiting due to salt-wasting leading to dehydration
and death • early pubic hair and rapid growth in
childhood • precocious puberty or failure of puberty
to occur (sexual infantilism: absent or delayed puberty)
• excessive facial hair, virilization, and/or menstrual
irregularity in adolescence • infertility due to
anovulation • hypertension
Craniosynostosis ( non
specific) C749-FGFR 3
Craniosynostosis, is a medical condition in which some or
all of the sutures in the skull of an infant or child close
too early, causing problems with normal brain and skull growth.
It can result in craniostenosis, which is the skull deformity
caused by the premature closure of the cranial sutures. Also
intracranial pressure can be increased.
Crigler Najjar Syn.- UGT1A1 gene sequencing
Crigler-Najjar Syndrome or CNS is a rare disorder affecting
the metabolism of bilirubin, a chemical formed from the breakdown
of blood. The disorder results in an inherited form of non-hemolytic
jaundice often leading to brain damage in infants.
Cruozon disease: FGFR
2 mutation (Ser 354 Cys)
Crouzon Syndrome is a genetic disorder known as a branchial
arch syndrome. Specifically, this syndrome affects the first
branchial (or pharyngeal) arch, which is the precursor of
the maxilla and mandible. Since the branchial arches are important
developmental features in a growing embryo, disturbances in
their development create lasting and widespread effects. Low-set
ear is a typical characteristic, as in all of the disorders
which are called branchial arch syndromes. The most notable
characteristic of Crouzon Syndrome is cranial synostosis,
as described above, but it usually presents as brachycephaly,
which results in the appearance of a short and broad head.
Cystic Fibrosis-
Diagnosis (Delta 508 mutation)
Cystic fibrosis (also known
as CF, mucoviscoidosis, or mucoviscidosis)
is a hereditary disease affecting the exocrine (mucus) glands
of the lungs, liver, pancreas, and intestines, causing progressive
disability due to multisystem failure.
Thick mucus production results in frequent lung infections.
Diminished secretion of pancreatic enzymes is the main cause
of poor growth, fatty diarrhea, and deficiency in fat-soluble
vitamins. Males can be infertile due to the condition congenital
bilateral absence of the vas deferens. Often, symptoms of
CF appear in infancy and childhood. Meconium ileus is a typical
finding in newborn babies with CF.
Cystic Megalencephaly- MLC1 gene sequencing
Cystic leukoencephalopathy with megalencephaly
is a newly described entity with mild clinical involvement.
Patients suffer from developmental problems and seizures in
childhood. Progression is gradual into adulthood.
Deafness Connexin 26
gene-sequencing
Hearing loss is extremely common and can
present at any time from infancy to old age. About 1 in 1000
infants has profound hearing impairment, with half thought
to be of genetic origin. Many deafness genes exist, but the
most common cause of hearing loss in American and European
populations is a mutation in the connexin 26 (Cx26) gene.
Cx26 has a carrier rate of 3%, similar to that for cystic
fibrosis, and it causes about 20% of childhood deafness. Mutations
in Cx26 cause congenital syndromic and nonsyndromic deafness—that
is, the deafness is not accompanied by other symptoms, such
as blindness. DMD
deletion testing - 18 exons
Duchenne muscular dystrophy (DMD) is a severe
recessive x-linked form of muscular dystrophy that is characterized
by rapid progression of muscle degeneration, eventually leading
to loss in ambulation, paralysis, and death. This affliction
affects one in 3500 males, making it the most prevalent of
muscular dystrophies. In general, males are only afflicted,
though females can be carriers. The disorder is caused by
a mutation in the gene DMD, located in humans on the X chromosome.
The DMD gene codes for the protein dystrophin, an important
structural component within muscle tissue. Dystrophin provides
structural stability to the dystroglycan complex (DGC), located
on the cell membrane.
Symptoms usually appear in male children before age 6 and
may be visible in early infancy. Progressive proximal muscle
weakness of the legs and pelvis associated with a loss of
muscle mass is observed first. Eventually this weakness spreads
to the arms, neck, and other areas. Early signs may include
pseudohypertrophy (enlargement of calf muscles), low endurance,
and difficulties in standing unaided or inability to ascend
staircases. As the condition progresses, muscle tissue experiences
wasting and is eventually replaced by fat and fibrotic tissue
(fibrosis). By age 10, braces may be required to aide in walking
but most patients are wheelchair dependent by age 12. Later
symptoms may include abnormal bone development that lead to
skeletal deformities, including curvature of the spine. Due
to progressive deterioration of muscle, loss of movement occurs
eventually leading to paralysis. Intellectual impairment may
also be present but does not progressively worsen as the child
ages. The average life expectancy for patients afflicted with
DMD varies from early teens to age mid 30s. There have been
reports of DMD patients surviving past the age of 40 and even
50. Dystonia
(DYT 1 gene- common deletion)
Dystonia is a neurological movement disorder
in which sustained muscle contractions cause twisting and
repetitive movements or abnormal postures.[1] The disorder
may be inherited or caused by other factors such as birth-related
or other physical trauma, infection, poisoning (eg. lead poisoning)
or reaction to drugs. Symptoms vary according to the kind
of dystonia involved. In most cases, dystonia tends to lead
to abnormal posturing, particularly on movement. Many sufferers
have continuous pain, cramping and relentless muscle spasms
due to involuntary muscle movements.
Ectodermal dysplasia X- linked –PND
by linkage +MCC
Ectodermal Dysplasia (ED) is not a single
disorder, but a group of closely related conditions of which
more than one hundred and sixty different syndromes have been
identified. The Ectodermal Dysplasias (EDs) are genetic disorders
affecting the development or function of the teeth, hair,
nails and sweat glands. Depending on the particular syndrome
ED can also affect the skin, the lens or retina of the eye,
parts of the inner ear, the development of fingers and toes,
the nerves and other parts of the body.
Epidermolysis bullosa dystrophia (PND- by
linkage)
Epidermolysis bullosa dystrophica includes
a rare group of inherited diseases involving blistering of
the skin. The mucous membranes or linings of the cavities
of the body that open to the outside, such as the mouth and
the surfaces of the eyes, are also sometimes involved. Epidermolysis
bullosa is characterised by fragile skin that forms blisters
usually following physical contact like a bump or graze, although
can also occur spontaneously. Epidermolysis bullosa can vary
in severity from minor blistering through to severe, where
constant, massive blistering and scarring occur. In severe
forms epidermolysis bullosa can result in: •
breathing or swallowing difficulties • death
• malnutrition due to feeding difficulties •
nail changes • scarring of the involved areas which
may result in movement difficulties • skin atrophy
(reduced amount of skin) at the site of blisters •
skin cancer • vision impairment.
Factor V Leiden
Factor V Leiden (sometimes Factor VLeiden)
is the name given to a variant of human factor V that causes
a hypercoagulability disorder. The excessive clotting that
occurs in this disorder is almost always restricted to the
veins, where the clotting may cause a deep vein thrombosis
(DVT). If the venous clots break off, these clots can travel
through the heart to the lung, where they block a pulmonary
blood vessel and cause a pulmonary embolism. Women with the
disorder have an increased risk of miscarriage and stillbirth.
It is extremely rare for this disorder to cause the formation
of clots in arteries that can lead to stroke or heart attack,
though rare a "mini-stroke" known as a transient
ischemic attack is more common.
Familial hypercholesterolemia (linkage,
Prenatal)
Familial hypercholesterolemia (abbreviated
FH, also spelled familial hypercholesterolaemia) is a genetic
disorder characterized by high cholesterol levels, specifically
very high low-density lipoprotein (LDL, "bad cholesterol")
levels, in the blood and early cardiovascular disease. High
cholesterol levels normally do not cause any symptoms. Cholesterol
may be deposited in various places in the body that are visible
from the outside, such as in yellowish patches around the
eyelids (xanthelasma palpebrarum), the outer margin of the
iris (arcus senilis corneae) and in the form of lumps in the
tendons of the hands, elbows, knees and feet, particularly
the Achilles tendon (tendon xanthoma).
FGFR 3 gene sequencing (Ach, Hypochond,
Thanatophoric dw)
Mutation in FGR 3 gene causes various dwarfism.
These condition affects the conversion of cartilage into bone
(a process called ossification), particularly in the long
bones of the arms and legs. Hypochondroplasia is similar to
another skeletal disorder called achondroplasia, but the features
tend to be milder.
All people with hypochondroplasia have short stature. The
adult height for men with this condition ranges from 138 centimeters
to 165 centimeters (4 feet, 6 inches to 5 feet, 5 inches).
The height range for adult women is 128 centimeters to 151
centimeters (4 feet, 2 inches to 4 feet, 11 inches).
People with hypochondroplasia have short arms and legs and
broad, short hands and feet. Other characteristic features
include a large head, limited range of motion at the elbows,
a sway of the lower back (lordosis), and bowed legs. These
signs are generally less pronounced than those seen with achondroplasia
and may not be noticeable until early or middle childhood.
Some studies have reported that a small percentage of people
with hypochondroplasia have mild to moderate mental retardation
or learning disabilities, but other studies have produced
conflicting results. Folate
Polymorphism 3' 5 MTHFR ( 677C>T, 1298 A>C)
Folate plays an important role in carcinogenesis.
The enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR),
encoded by the MTHFR gene, is involved in this process. Mutation
on the gene results various consequences including endometrial
cancer, Down's syndrome, Coronary Heart disease or leukemia.
Fragile X Screen-
PCR based
Fargile X syndrome is a genetic syndrome
which results in a spectrum (from none to severe) of characteristic
physical, intellectual, emotional and behavioural features.
Aside from intellectual disability, prominent characteristics
of the syndrome include an elongated face, large or protruding
ears, flat feet, larger testicles in men (macroorchidism),
and low muscle tone. Speech may include cluttered speech or
nervous speech[7]. Behavioral characteristics may include
stereotypic movements (e.g., hand-flapping) and atypical social
development, particularly shyness and limited eye contact.
Some individuals with the fragile X syndrome also meet the
diagnostic criteria for autism. Most females experience symptoms
to a lesser degree because of their second X-chromosome, however
they can develop just as severe symptoms. While full mutation
males tend to present with severe intellectual disability,
the symptoms of full mutation females run the gamut of minimally
affected to severe intellectual disability, which may explain
why females are underdiagnosed relative to males.
In short, similarities between X-linked recessive
inheritance and fragile X are
1. Males are dominantly affected
2. Females (mothers) are obligatory carriers if a male child
is affected, but not necessarily if female children are
Friedreich Ataxia
Friedreich's ataxia is an inherited disease
that causes progressive damage to the nervous system resulting
in symptoms ranging from muscle weakness and speech problems
to heart disease. Ataxia results from the degeneration of
nerve tissue in the spinal cord and of nerves that control
muscle movement in the arms and legs. Symptoms usually begin
between the ages of 5 and 15 but can appear as early as 18
months or as late as 30 years of age. The first symptom is
usually difficulty in walking. The ataxia gradually worsens
and slowly spreads to the arms and then the trunk. Foot deformities
such as clubfoot, flexion (involuntary bending) of the toes,
hammer toes, or foot inversion (turning in) may be early signs.
Rapid, rhythmic, involuntary movements of the eyeball are
common. Most people with Friedreich's ataxia develop scoliosis
(a curving of the spine to one side), which, if severe, may
impair breathing. Other symptoms include chest pain, shortness
of breath, and heart palpitations
G-6-PD one mutation
G6PD deficiency is an inherited condition
in which the body doesn't have enough of the enzyme glucose-6-phosphate
dehydrogenase, or G6PD, which helps red blood cells (RBCs)
function normally. This deficiency can cause hemolytic anemia,
usually after exposure to certain medications, foods, or even
infections.
Most people with G6PD deficiency don't have any symptoms,
while others develop symptoms of anemia only after RBCs have
been destroyed, a condition called hemolysis. In these cases,
the symptoms disappear once the cause, or trigger, is removed.
In rare cases, G6PD deficiency leads to chronic anemia.
Galatosemia gene
sequencing (GALT)
Galactosemia (OMIM 230400) is a defect in
the metabolism of galactose resulting in elevated levels of
galactose and derivatives such as galactose-1-phosphate and
galactitol. Severity of this disorder is quite variable, but
the most severe “classic” form with onset in early
infancy is characterized by vomiting, diarrhea, jaundice,
cataracts, hepatomegaly and sepsis. If the amount of lactose
in the diet is not reduced, these symptoms progress to death.
Even in surviving patients, ovarian failure and lifelong speech
and cognitive disabilities are expected.
Gaucher's disease (4 common mutations)
Gaucher disease is an inherited metabolic
disorder in which harmful quantities of a fatty substance
called glucocerebroside accumulate in the spleen, liver, lungs,
bone marrow, and sometimes in the brain. There are three types
of Gaucher disease. The first category, called type 1, is
by far the most common. Patients in this group usually bruise
easily and experience fatigue due to anemia and low blood
platelets. They also have an enlarged liver and spleen, skeletal
disorders, and, in some instances, lung and kidney impairment.
There are no signs of brain involvement. Symptoms can appear
at any age. In type 2 Gaucher disease, liver and spleen enlargement
are apparent by 3 months of age. Patients have extensive and
progressive brain damage and usually die by 2 years of age.
In the third category, called type 3, liver and spleen enlargement
is variable, and signs of brain involvement such as seizures
gradually become apparent. All Gaucher patients exhibit a
deficiency of an enzyme called glucocerebrosidase that is
involved in the breakdown and recycling of glucocerebroside.
The buildup of this fatty material within cells prevents the
cells and organs from functioning properly. Gaucher disease
is one of several lipid storage diseases.
Gilbert's disease (UGT1A1 Promoter polymorphism)
Gilbert's syndrome, often shortened to the
acronym GS, is the most common hereditary cause of increased
bilirubin, and is found in up to 5% of the population (though
some Gastroenterologists maintain that it is closer to 10%).
The main symptom is otherwise harmless jaundice which does
not require treatment, caused by elevated levels of unconjugated
bilirubin in the bloodstream (hyperbilirubinemia).
The source of this hyperbilirubinemia is reduced activity
of the enzyme glucuronyltransferase which conjugates bilirubin
and some other lipophilic molecules. Conjugation renders the
bilirubin water-soluble, after which it is excreted in bile
into the duodenum.
Gilbert's syndrome produces an elevated level of unconjugated
bilirubin in the bloodstream but normally has no serious consequence.
Mild jaundice may appear under conditions of exertion, stress,
fasting, and infections, but the condition is otherwise asymptomatic.
It has been reported that GS may contribute to an accelerated
onset of neonatal jaundice
The enzymes that are defective in GS (UGT1A1) are also responsible
for some of the liver's ability to detoxify certain drugs.
For example, Gilbert's syndrome is associated with severe
diarrhea and neutropenia in patients who are treated with
irinotecan, which is metabolized by UGT1A1.
While paracetamol (acetaminophen) is not metabolized by UGT1A1,
it is metabolized by one of the other enzymes also deficient
in some people with GS. A subset of people with GS may have
an increased risk of paracetamol toxicity.
Glycogen storage 1a gene sequencing
Glycogen storage disease (synonyms: glycogenosis,
dextrinosis) is any one of several inborn errors of metabolism
that result from enzyme defects that affect the processing
of glycogen synthesis or breakdown within muscles, liver,
and other cell types. Hallorverden-Spantz
disease (PND by linkage)
Hallervorden-Spatz disease (HSD) is a rare
disorder characterized by progressive extrapyramidal dysfunction
and dementia. Onset is most commonly in late childhood or
early adolescence, but cases with adult onset have been described.
The disease can be familial or sporadic. When familial, it
is inherited recessively and has been linked to chromosome
20. Recently, a mutation in the pantothenate kinase (PANK2)
gene on band 20p13 has been described in patients with typical
HSD.
HSD is relentlessly progressive. The course is characterized
by progressive dementia, corticospinal signs (eg, spasticity,
hyperreflexia), and extrapyramidal signs including rigidity,
dystonia, and choreoathetosis. Affected individuals typically
die in the second or third decade. The course of the disease
usually proceeds over 10-12 years, but case reports describe
patients surviving 30 years Hypochondroplasia
(Sequencing)
Hypochondroplasia is a form of short-limbed
dwarfism. This condition affects the conversion of cartilage
into bone (a process called ossification), particularly in
the long bones of the arms and legs. Hypochondroplasia is
similar to another skeletal disorder called achondroplasia,
but the features tend to be milder.
All people with hypochondroplasia have short stature. The
adult height for men with this condition ranges from 138 centimeters
to 165 centimeters (4 feet, 6 inches to 5 feet, 5 inches).
The height range for adult women is 128 centimeters to 151
centimeters (4 feet, 2 inches to 4 feet, 11 inches).
People with hypochondroplasia have short arms and legs and
broad, short hands and feet. Other characteristic features
include a large head, limited range of motion at the elbows,
a sway of the lower back (lordosis), and bowed legs. These
signs are generally less pronounced than those seen with achondroplasia
and may not be noticeable until early or middle childhood.
Some studies have reported that a small percentage of people
with hypochondroplasia have mild to moderate mental retardation
or learning disabilities, but other studies have produced
conflicting results.
Mutations in the FGFR3 gene cause hypochondroplasia.
Hemochromatosis
(2 mutations in HFE gene)
Hemochromatosis is the most common form
of iron overload disease. Primary hemochromatosis, also called
hereditary hemochromatosis, is an inherited disease. Secondary
hemochromatosis is caused by anemia, alcoholism, and other
disorders.
Juvenile hemochromatosis and neonatal hemochromatosis are
two additional forms of the disease. Juvenile hemochromatosis
leads to severe iron overload and liver and heart disease
in adolescents and young adults between the ages of 15 and
30. The neonatal form causes rapid iron buildup in a baby’s
liver that can lead to death.
Hemochromatosis causes the body to absorb and store too much
iron. The extra iron builds up in the body’s organs
and damages them. Without treatment, the disease can cause
the liver, heart, and pancreas to fail.
Iron is an essential nutrient found in many foods. The greatest
amount is found in red meat and iron-fortified breads and
cereals. In the body, iron becomes part of hemoglobin, a molecule
in the blood that transports oxygen from the lungs to all
body tissues.
Healthy people usually absorb about 10 percent of the iron
contained in the food they eat, which meets normal dietary
requirements. People with hemochromatosis absorb up to 30
percent of iron. Over time, they absorb and retain between
five to 20 times more iron than the body needs.
Because the body has no natural way to rid itself of the excess
iron, it is stored in body tissues, specifically the liver,
heart, and pancreas.
Joint pain is the most common complaint of people with hemochromatosis.
Other common symptoms include fatigue, lack of energy, abdominal
pain, loss of sex drive, and heart problems. However, many
people have no symptoms when they are diagnosed.
If the disease is not detected and treated early, iron may
accumulate in body tissues and eventually lead to serious
problems such as • arthritis • liver
disease, including an enlarged liver, cirrhosis, cancer, and
liver failure • damage to the pancreas, possibly
causing diabetes • heart abnormalities, such as
irregular heart rhythms or congestive heart failure •
impotence • early menopause • abnormal
pigmentation of the skin, making it look gray or bronze
• thyroid deficiency • damage to the adrenal
glands Hemophilia
A/B, Carrier test
Haemophilia (also spelled as hemophilia,
from the Greek haima "blood" and philia "to
love"[1]) is a group of hereditary genetic disorders
that impair the body's ability to control blood clotting or
coagulation. In its most common form, Hemophilia A, clotting
factor VIII is absent. In Haemophilia B, factor IX is deficient.
Hemophilia A occurs in about 1 in 5,000–10,000 male
births[2], while Hemophilia B occurs at about 1 in about 20,000–34,000.
The effects of this sex-linked, X chromosome disorder are
manifested almost entirely in males, although the gene for
the disorder is inherited from the mother. Females have two
X chromosomes while males have only one, lacking a 'back up'
copy for the defective gene. Females are therefore almost
exclusively carriers of the disorder, and may have inherited
it from either their mother or father. In about 30% of cases
of Hemophilia B, however, there is no family history of the
disorder and the condition is the result of a spontaneous
gene mutation[2]. A mother who is a carrier has a 50% chance
of passing the faulty X chromosome to her daughter, while
an affected father will always pass on the affected gene to
his daughters. A son cannot inherit the defective gene from
his father.
These genetic deficiencies may lower blood plasma clotting
factor levels of coagulation factors needed for a normal clotting
process. When a blood vessel is injured, a temporary scab
does form, but the missing coagulation factors prevent fibrin
formation which is necessary to maintain the blood clot. Thus
a haemophiliac does not bleed more intensely than a normal
person, but for a much longer amount of time. In severe haemophiliacs
even a minor injury could result in blood loss lasting days,
weeks, or not ever healing completely. The critical risk here
is with normally small injuries which, due to missing factor
VIII, take long times to heal. In areas such as the brain
or inside joints this can be fatal or permanently debilitating.
The bleeding with external injury is normal, but incidence
of late re-bleeding and internal bleeding is increased, especially
into muscles, joints, or bleeding into closed spaces. Major
complications include hemarthrosis, hemorrhage, gastrointestinal
bleeding, and menorrhagia. Hemophilia
A/B, (Prenatal diagnosis)
Haemophilia (also spelled as hemophilia,
from the Greek haima "blood" and philia "to
love"[1]) is a group of hereditary genetic disorders
that impair the body's ability to control blood clotting or
coagulation. In its most common form, Hemophilia A, clotting
factor VIII is absent. In Haemophilia B, factor IX is deficient.
Hemophilia A occurs in about 1 in 5,000–10,000 male
births[2], while Hemophilia B occurs at about 1 in about 20,000–34,000.
The effects of this sex-linked, X chromosome disorder are
manifested almost entirely in males, although the gene for
the disorder is inherited from the mother. Females have two
X chromosomes while males have only one, lacking a 'back up'
copy for the defective gene. Females are therefore almost
exclusively carriers of the disorder, and may have inherited
it from either their mother or father. In about 30% of cases
of Hemophilia B, however, there is no family history of the
disorder and the condition is the result of a spontaneous
gene mutation[2]. A mother who is a carrier has a 50% chance
of passing the faulty X chromosome to her daughter, while
an affected father will always pass on the affected gene to
his daughters. A son cannot inherit the defective gene from
his father.
These genetic deficiencies may lower blood plasma clotting
factor levels of coagulation factors needed for a normal clotting
process. When a blood vessel is injured, a temporary scab
does form, but the missing coagulation factors prevent fibrin
formation which is necessary to maintain the blood clot. Thus
a haemophiliac does not bleed more intensely than a normal
person, but for a much longer amount of time. In severe haemophiliacs
even a minor injury could result in blood loss lasting days,
weeks, or not ever healing completely. The critical risk here
is with normally small injuries which, due to missing factor
VIII, take long times to heal. In areas such as the brain
or inside joints this can be fatal or permanently debilitating.
The bleeding with external injury is normal, but incidence
of late re-bleeding and internal bleeding is increased, especially
into muscles, joints, or bleeding into closed spaces. Major
complications include hemarthrosis, hemorrhage, gastrointestinal
bleeding, and menorrhagia.
Prenatal testing, such as amniocentesis, is available to pregnant
women who may be carriers of the condition.
Herpes Virus infection (PCR)
Herpes simplex virus 1 and 2 (HSV-1 and
HSV-2) are two species of the herpes virus family, Herpesviridae,
which cause infections in humans. Eight members of herpesviridae
infect humans to cause a variety of illnesses including cold
sores, chickenpox or varicella, shingles or herpes zoster
(VZV), cytomegalovirus (CMV), and various cancers, and can
cause brain inflammation (encephalitis). All viruses in the
herpes family produce life-long infections.
They are also called Human Herpes Virus 1 and 2 (HHV-1 and
HHV-2) and are neurotropic and neuroinvasive viruses; they
enter and hide in the human nervous system, accounting for
their durability in the human body. HSV-1 is commonly associated
with herpes outbreaks of the face known as cold sores or fever
blisters, whereas HSV-2 is more often associated with genital
herpes.
An infection by a herpes simplex virus is marked by watery
blisters in the skin or mucous membranes of the mouth, lips
or genitals.[1] Lesions heal with a scab characteristic of
herpetic disease. However, the infection is persistent and
symptoms may recur periodically as outbreaks of sores near
the site of original infection. After the initial, or primary,
infection, HSV becomes latent in the cell bodies of nerves
in the area. Some infected people experience sporadic episodes
of viral reactivation, followed by transportation of the virus
via the nerve's axon to the skin, where virus replication
and shedding occurs.
Herpes is contagious if the carrier is producing and shedding
the virus. This is especially likely during an outbreak but
possible at other times. There is no cure yet, but there are
treatments which reduce the likelihood of viral shedding.
Hunter Syndrome
- deletions
Hunter syndrome is a rare genetic disorder
that occurs when an enzyme your body needs is either missing
or malfunctioning.
Because the body doesn't have adequate supplies of the enzyme
to break down certain complex molecules, the molecules build
up in harmful amounts in certain cells and tissues. The buildup
that occurs in Hunter syndrome eventually causes permanent,
progressive damage affecting appearance, mental development,
organ function and physical abilities.
Hunter syndrome appears in children as young as age 2. It
nearly always occurs in males, although it may occur in females.
Treatment of Hunter syndrome mostly involves management of
your symptoms and complications. Enzyme replacement therapy
and other emerging therapies may offer more help in the future.
Hunter syndrome is one type of a group of inherited metabolic
disorders called mucopolysaccharidosis (MPS), and Hunter syndrome
is referred to as MPS II. There are two subtypes of Hunter
syndrome, MPS IIA and MPS IIB. Symptoms vary according to
subtype. Type MPS IIA (early onset)
Early-onset Hunter syndrome (MPS IIA) is the more severe of
the two types and usually appears around age 2 and up to age
4. This form of the disorder may result in profound mental
retardation by late childhood. Children with this form of
the syndrome usually don't survive beyond their teens.
Signs and symptoms of MPS IIA include:
• A decline in development, which usually appears between
ages 1 1/2 and 3, followed by a progressive loss of skills
• Coarse facial features, including thickening of the
lips, tongue and nostrils • Abnormal bone size or shape
and other skeletal irregularities • Enlarged internal
organs, such as the liver and spleen, resulting in a distended
abdomen • Respiratory difficulties including sleep apnea,
a condition in which breathing intermittently stops during
sleep • Cardiovascular disorders, such as progressive
thickening of heart valves, high blood pressure (hypertension)
and obstruction of blood vessels • Vision loss or impairment
from degeneration of cells that capture light and buildup
of cellular debris in the brain causing pressure on the optic
nerve and eye • Skin lesions on the back and upper arms
• Progressive loss of hearing • Aggressive behavior
• Stunted growth • Joint stiffness • Diarrhea
Type MPS IIB (late onset)
Late-onset Hunter syndrome (MPS IIB) is milder and causes
less severe symptoms that appear much later. This form is
usually diagnosed after age 10, and may not be detected until
adulthood. Intellectual and social development usually is
nearly normal, but the condition may affect verbal and reading
skills. People with this type of Hunter syndrome can live
into their 50s. Signs and symptoms of MPS
IIB include: • Abnormal bone size or shape and
other skeletal irregularities, but less severe than in MPS
IIA • Somewhat stunted growth • Poor peripheral
vision • Joint stiffness • Hearing loss • Diarrhea
• Sleep apnea Huntington
disease
Huntington diseases is an inherited genetic
neurological disorder characterized by abnormally uncoordinated,
jerky body movements called chorea and a decline in some mental
abilities, which can lead to affected aspects of behavior.
As the disorder progresses, it can cause complications that
significantly reduce life expectancy. The exact mechanism
of HD is unproven and there is currently no proven cure, so
symptoms are managed with a range of medications to treat
individual symptoms and supportive services. Global incidence
varies, from 3 to 7 per 100,000 people of Western European
descent, down to 1 per 1,000,000 of Asian and African descent.
The onset of physical symptoms in Huntington's disease can
occur at any age, but commonly occurs in a person's thirties
to early fifties. If symptoms become noticeable before a person
is twenty, their condition is known as juvenile HD.
Huntington's disease is one of several polyglutamine diseases
caused by the length of a repeated section of a gene exceeding
the normal range. The huntingtin gene (HTT) normally provides
the information to produce Huntingtin protein, but when affected,
produces mutant Huntingtin (mHTT) instead. The presence of
mHTT causes an increase in the rate of neuronal cell death
in select areas of the brain, affecting neurological functions.
The disorder is named after George Huntington, the American
physician who first described it in 1872. In 1983 a marker
for the altered DNA causing the disease was found, followed
a decade later by discovery of a single, causal, gene. As
it was caused by a single gene, an accurate genetic test for
HD was developed, this was one of the first inherited genetic
disorders for which this was possible. Due to the availability
of this test, and similar characteristics with other neurological
disorders, HD research has been increasing over time.
Physical symptoms are usually the first to cause problems
and to be noticed, but at this point they are usually accompanied
by cognitive and psychiatric ones that are often not recognized.
Almost everyone with Huntington's disease eventually exhibits
all physical symptoms, but cognitive and psychiatric symptoms
vary significantly between individuals
Hypochondroplasia-common mutation C1620A
in FGFR3
Hypochondroplasia is a form of short-limbed
dwarfism. This condition affects the conversion of cartilage
into bone (a process called ossification), particularly in
the long bones of the arms and legs. Hypochondroplasia is
similar to another skeletal disorder called achondroplasia,
but the features tend to be milder.
All people with hypochondroplasia have short stature. The
adult height for men with this condition ranges from 138 centimeters
to 165 centimeters (4 feet, 6 inches to 5 feet, 5 inches).
The height range for adult women is 128 centimeters to 151
centimeters (4 feet, 2 inches to 4 feet, 11 inches).
People with hypochondroplasia have short arms and legs and
broad, short hands and feet. Other characteristic features
include a large head, limited range of motion at the elbows,
a sway of the lower back (lordosis), and bowed legs. These
signs are generally less pronounced than those seen with achondroplasia
and may not be noticeable until early or middle childhood.
Some studies have reported that a small percentage of people
with hypochondroplasia have mild to moderate mental retardation
or learning disabilities, but other studies have produced
conflicting results.
Mutations in the FGFR3 gene cause hypochondroplasia.
Jak 2 mutation
Jak 2 is an intracellular tyrosine kinase
of the non-receptor type that associates with the intracellular
domains of cytokine receptors; JAK2 is the predominant JAK
kinase activated in response to several growth factors and
cytokines such as IL-3, GM-CSF and erythropoietin; it has
been found to be constitutively associated with the prolactin
receptor and is required for responses to gamma interferon.
This enzyme is part of a messaging system inside the bone-producing
cells (or stem cells) in our bone marrow. When a mutation
occurs, the messaging system goes haywire, causing the stem
cells to produce too many blood cells, resulting in myeloproliferative
disorders.
Researchers are currently testing "designer drugs"
that target the JAK2 mutation. We hope in the future these
drugs will control or cure myeloproliferative disorders.
Krabbes disease-
common deletion
Krabbe disease (also known as globoid cell
leukodystrophy or galactosylceramide lipidosis) is a rare,
often fatal degenerative disorder that affects the myelin
sheath of the nervous system. This condition is inherited
in an autosomal recessive pattern.
Krabbe disease is caused by mutations in the GALC gene, which
causes a deficiency of an enzyme called galactosylceramidase.
The buildup of unmetabolized lipids affects the growth of
the nerve's protective myelin sheath (the covering that insulates
many nerves) and causes severe degeneration of motor skills.
As part of a group of disorders known as leukodystrophies,
Krabbe disease results from the imperfect growth and development
of myelin.
Infants with Krabbe disease are normal at birth. Symptoms
begin between the ages of 3 and 6 months with irritability,
fevers, limb stiffness, seizures, feeding difficulties, vomiting,
and slowing of mental and motor development. In the first
stages of the disease, doctors often mistake the symptoms
for those of cerebral palsy. Other symptoms include muscle
weakness, spasticity, deafness, optic atrophy and blindness,
paralysis, and difficulty when swallowing. Prolonged weight
loss may also occur. There are also juvenile- and adult-onset
cases of Krabbe disease, which have similar symptoms but slower
progression. Leb
Hered Optic Atrophy- 3 mutations
Lowe Syndrome - linkage
studies/ family
Lowe Syndrome (LS) is a rare genetic condition
that causes physical and mental handicaps, and medical problems.
The condition became known as "Lowe syndrome" named after
Dr. Charles Lowe, the senior member of the group that described
it. Because of the three major organ systems involved (eyes,
brain, and kidney), it is also known as OCRL (oculo-cerebro-renal)
syndrome.
Boys with Lowe Syndrome are born with cataracts in both eyes,
which are usually removed at a few months of age. Most boys
are fitted with glasses, contacts, or a combination of the
two. Glaucoma is present in about 50% of the boys with Lowe
syndrome, though usually not at birth. Prescription eye drop
and/or surgery is required to maintain appropriate eye pressure
in these cases.
While not present at birth, many Lowe Syndrome boys develop
kidney problems at approximately one year of age. This is
characterized by the abnormal loss of certain substances into
the urine, including bicarbonate, sodium, potassium, amino
acids, organic acids, albumin and other small proteins, calcium,
phosphate, glucose, and L-carnitine. This problem is known
as Fanconi-type renal tubular dysfunction and can also be
seen in certain other diseases and syndromes. In Lowe syndrome,
the Fanconi syndrome may be mild and involve only a few substances
or may be severe and involve large losses of many substances.
Medications can be prescribed to replace the lost substances.
Lowe syndrome is a hereditary condition that affects only
males. It is caused by a single defective gene (an alteration
or "mutation") in a gene called OCRL1. Because of
this defective gene, an essential enzyme called PIP2-5-phosphatase
is not produced. This is the underlying cause of Lowe syndrome.
Much research has taken place in the last few years. The gene
has been mapped and the defecient enzyme has been identified,
although its role is not fully understood.
Maternal Cell Contamination
When performing genetic analysis on products of conception,
an amniocentesis sample or villous sampling, it is always
possible that the findings may represent contamination with
maternal tissue rather than reflect fetal findings.
Maternal cell contamination may occur:
(1) if maternal tissue is sampled rather than fetal
(2) fetal tissue is nonviable
Maternal cell contamination should be suspected if:
(1) the fetus is necrotic
(2) the results of culture are XX but the phenotype is male
Marfan Syndrome-linkage
studies
The Marfan syndrome is a connective tissue
disorder. Connective tissue provides substance and support
to tendons, ligaments, blood vessel walls, cartilage, heart
valves and many other structures. In the Marfan syndrome,
the chemical makeup of the connective tissue isn't normal.
As a result, many of these structures aren't as stiff as they
should be.
The Marfan syndrome is inherited and affects many parts of
the body. There's no single conclusive test for diagnosing
it, but people who have it often have many similar traits.
Besides perhaps having heart problems, people with the Marfan
syndrome are often tall and thin. They also may have slender,
tapering fingers, long arms and legs, curvature of the spine
and eye problems. Sometimes the Marfan syndrome is so mild
that few (if any) symptoms exist. In the most severe cases,
which are rare, life-threatening problems may occur at any
age. MCAD
mutation (Medium chain acyl-coA dehyd)
Deficiency of an enzyme that makes it impossible
to digest certain kinds of fat. MCAD stands for medium-chain
acyl-CoA dehydrogenase. Children born with MCAD deficiency
cannot metabolize (digest) medium-chain fats such as coconut
oil. If undiagnosed, the disorder can lead to metabolic collapse,
coma and even death. Babies who survive run the risk of severe
brain damage. Treatment involves strict attention to what
the baby eats. The child has to avoid medium-chain fats in
the diet. It is a life-long disorder. The special formula
translates into a permanent diet change. MCAD deficiency affects
about 1 of every 15,000 babies born in the US.
The gene for MCAD is located on chromosome 1p31. Over 25 MCAD
gene variants have been reported. One of these gene variants,
the K304E MCAD mutation, accounts for the majority of MCAD
mutations identified to date. MCAD is an autosomal recessive
disorder. Therefore, individuals who are homozygous or compound
heterozygous for an MCAD mutation may have abnormal protein
product and subsequent inefficient enzymatic activity to metabolize
medium-chain fatty acids.
MCAD-deficient patients are at risk for a combination of the
following outcomes: hypoglycemia (Low blood sugar), vomiting,
lethargy, encephalopathy (brain disease), respiratory arrest,
hepatomegaly (enlarged liver), seizures, apnea, cardiac arrest,
coma, and sudden death. Long-term outcomes may include developmental
and behavioral disability, chronic muscle weakness, failure
to thrive, cerebral palsy, and attention deficit hyperactivity
disorder (ADHD).
A precipitating factor is needed for clinical symptoms to
present. It is often in times of metabolic stress induced
by fasting or infection, when the demands on fatty acid oxidation
are particularly high, that an MCAD-deficient patient may
present with symptoms. Factors that may contribute to presentation
and/or increased severity of clinical outcomes include prolonged
fasting, infections or recent immunization, age, and family
history of Sudden Infant Death Syndrome (SIDS) or MCAD deficiency.
MCAD mutations can be identified through DNA-based tests using
polymerase chain reaction (PCR) and therefore can be detected
in newborns by DNA analysis from newborn blood spots. Mass
screening for MCAD deficiency, however, is generally conducted
with the detection of abnormal metabolites in urine or blood
by tandem mass spectrometry . Typically, this technique is
used as an initial screening modality followed by confirmation
of MCAD deficiency with urine organic acid profile or DNA
mutation analysis. Testing for MCAD deficiency can be done
as one of the battery of newborn screening tests.
McArdle disease
(R49 X mutation, Sequencing)
A condition caused by an inborn deficiency
of muscle phosphorylase. There is an abnormal accumulation
of glycogen in muscle tissue. Symptoms are exercise intolerance
- muscular pain, fatigability - and muscle cramping. Rest
relieves the muscle pain and enables exercise to resume. However,
anaerobic activity leads to severe fixed contractures and
myoglobinuria from muscle breakdown which can lead to acute
renal failure. Size and initial power tone of muscle are normal
at outset of exercise. Onset usually in early childhood, although
diagnosis often not made until the second or third decade.
Affected people appear normal on presentation with exercise
intolerance but creatine kinase is raised. Many people experience
a worsening of symptoms after middle age when muscle wasting
may be seen. Unlike other types of glycogenosis the disease
is not fatal and the missing enzyme does not impair the functioning
of other body systems. Inheritance is autosomal recessive.
Dominant form rarely reported.
Merosin deficiency-linkage/ PND
Congenital muscular dystrophies (CMD) are
a heterogeneous group of autosomal recessively inherited diseases,
presenting at birth or within the first 6 months of life.
Initial signs include hypotonia, muscle weakness and the variable
appearance of contractures characterized by dystrophic changes
on skeletal-muscle biopsy. The heterogeneous nature of CMD
is reflected by differing degrees of motor developmental delay,
physical disability, muscle pathology, elevation of serum
creatine kinase (CK) and a variable presence of mental retardation
and structural brain defects. Thus, CMD is among the most
frequent autosomal recessively inherited neuromuscular disoders.
Congenital muscular dystrophies (CMDs) are a highly heterogeneous
group of neuromuscular disorders. A subgroup displays a specific
deficiency in a protein of the extracellular matrix, the 2
chain of laminin-2 (merosin). A number of mutations in the
gene encoding this protein have been identified in patients
who present with a severe phenotype and white matter changes.
Metaphyseal
Dysplasia-COL 10A gene sequencing
Metaphyseal dysplasia is a very rare disorder
in which the outer part of the shafts of long bones is unusually
thin with a tendency to fracture. Aside from valgus knee deformities
(commonly known as knock-knee), many patients with metaphyseal
dysplasia exhibit few or no symptoms. However, the disorder
comes in a variety of forms, some of which cause serious problems
including mental retardation, blindness, and deafness.
The list of signs and symptoms mentioned in various sources
for Multiple joint dislocations - metaphyseal dysplasia includes
the 17 symptoms listed below: • Dislocated hip
• Overly extended knee • Dislocated
joints • Large fontanelle • High arched
palate • Narrow palate • Low set ears
• Small jaw • Short stature •
Wormian bones • Abnormal thumb positioning
• Newborn teeth • Shagreen patch •
Lymphoedema • Metaphyseal anomaly •
Facial dysmorphism • Reduced skull calcification
Mytotonic dystrophy-
type 1-19q 13.3
Myotonic dystrophy (DM) is a chronic, slowly progressing,
highly variable inherited multisystemic disease that can manifest
at any age from birth to old age. It is characterized by wasting
of the muscles (muscular dystrophy), posterior subcapsular
iridescent cataracts (opacity of the lens of the eyes), heart
conduction defects, endocrine changes and myotonia (difficulty
relaxing a muscle). Most notably, the highly variable age
of onset decreases with successive generations. Thus the disease
shows at an earlier age in successive generations, a phenomenon
termed anticipation. Myotonic dystrophy (DM) is a chronic,
slowly progressing, highly variable inherited multisystemic
disease that can manifest at any age from birth to old age.
It is characterized by wasting of the muscles (muscular dystrophy),
posterior subcapsular iridescent cataracts (opacity of the
lens of the eyes), heart conduction defects, endocrine changes
and myotonia (difficulty relaxing a muscle). Most notably,
the highly variable age of onset decreases with successive
generations. Thus the disease shows at an earlier age in successive
generations, a phenomenon termed anticipation.
Presentation of symptoms varies considerably by form (DM1/DM2),
severity and even unusual DM2 phenotypes. DM1 patients often
present with myotonia, disabling distal weakness and severe
cognitive problems. DM2 patients commonly present with muscle
pain, stiffness, fatigue, or the development of proximal lower
extremity weakness (Day & al, 2003). The characteristic
pattern of weakness is different for DM1 and DM2: In DM1,
it is noted in face and jaw muscles, the drooping of the eyelids
(ptosis), weakness of the neck muscles, hands and lower legs.
In DM2, the weakness is more evident in proximal muscles,
those closer to the trunk of the body: neck, shoulders, hip
flexors and upper legs.
Noted DM1 symptoms which are considered less severe or common
for DM2 are problems with smooth muscle (including G.I. symptoms),
hypersomnia (daytime sleepiness), muscle wasting, dysphagia
and respiratory insufficiency. DM1 patients may experience
a more diverse range of cognitive problems than DM2. Depending
on what form they have and the degree of severity, DM1 cognitive
problems may range from developmental delays, learning problems,
language, speech, behaviour, apathy or hypersomnia. Cognitive
manifestations for DM2 include problems with executive function
(i.e. organization, concentration, word-finding etc) and hypersomnia.
Conduction abnormalities are more common in DM1 than DM2,
but all patients are advised to have an annual ECG. Insulin
resistance is a significant risk factor in both forms of the
disease for diabetes, cholesterol, heart, stroke, lipids,
fatty liver, etc.
Testing for insulin resistance must be at least 3 hours and
include serial monitoring of the lipid profile and intermittent
assessment of oral glucose tolerance testing as per the report
from the 140th ENMC International Workshop: Myotonic Dystrophy
DM2/PROMM and other myotonic dystrophies with guidelines on
management (2006) Diabetes type 2 is suspected of being more
common in DM2 than in DM1. Generally far fewer DM2 patients
require assistive devices (canes, walkers, wheelchairs, scooters)
than in DM1, though they experience increasing difficulties
climbing stairs as the disease progresses, and falling or
stumbling may sometimes be reported.
Mytotonic dystrophy- type 2- 3q 21
NCL -infantile (2 mutation)
NCL, which is referred to as Batten disease, is a neurodegenerative
disease that affects infants and young children. Two forms
of NCL, infantile and late infantile, are caused by the deficiency
of a lysosomal enzyme. Infantile and late infantile NCL are
brought on by inherited genetic mutations in the CLN1 gene,
which codes for palmitoyl-protein thioesterase 1 (PPT1) and
in the CLN2 gene, which codes for tripeptidyl peptidase I
(TPP-I), respectively. The Company has completed enrollment
and dosing of a six-patient Phase I clinical trial at Oregon
Health & Science University Doernbecher Children's Hospital
to evaluate the safety and preliminary efficacy of its HuCNS-SC
product candidate as a treatment for infantile and late infantile
NCL. In addition to evaluating the safety of HuCNS-SC cells,
the trial will also evaluate the ability of the cells to affect
the progression of the disease.
NCL, or Batten disease, is one of a group of approximately
46 lysosomal storage diseases (LSDs). All LSDs are caused
by defective or missing proteins involved in lysosomal function
and some LSDs can be treated by enzyme replacement therapies.
Examples of enzyme replacement products already approved are
Cerezymetm for Gaucher disease, Fabryzymetm for Fabry disease,
Myozyme for Pompe disease, Aldurazymetm for MPS I and Naglazymetm
for MPS VI. All of these approved products, however, address
LSDs, which primarily affect peripheral organs and not the
central nervous system. Stem cells treat various spinal cord
indications using a mouse model of spinal cord injury. Inspection
of the spinal cords from the treated mice showed significant
levels of human neural cells derived from the transplanted
stem cells. Some of these cells were oligodendrocytes, the
specialized neural cell that forms the myelin sheath around
axons, while others had become neurons and showed evidence
of synapse formation, a requirement for proper neuronal function.
Neuroblastomatosis
(linkage, PND)
Parkinson disease (Gly
19 ser mutation, by sequencing)
Parkinson's disease (also known as Parkinson
disease or PD) is a degenerative disorder of the central nervous
system that often impairs the sufferer's motor skills and
speech, as well as other functions.
Parkinson's disease belongs to a group of conditions called
movement disorders. It is characterized by muscle rigidity,
tremor, a slowing of physical movement (bradykinesia) and,
in extreme cases, a loss of physical movement (akinesia).
The primary symptoms are the results of decreased stimulation
of the motor cortex by the basal ganglia, normally caused
by the insufficient formation and action of dopamine, which
is produced in the dopaminergic neurons of the brain. Secondary
symptoms may include high level cognitive dysfunction and
subtle language problems. PD is both chronic and progressive.
PD is the most common cause of chronic progressive parkinsonism,
a term which refers to the syndrome of tremor, rigidity, bradykinesia
and postural instability. PD is also called "primary
parkinsonism" or "idiopathic PD" (classically
meaning having no known cause although this term is not strictly
true in light of the plethora of newly discovered genetic
mutations). While many forms of parkinsonism are "idiopathic",
"secondary" cases may result from toxicity most
notably of drugs, head trauma, or other medical disorders.
The disease is named after English physician James Parkinson;
who made a detailed description of the disease in his essay:
"An Essay on the Shaking Palsy".
Parkinson disease affects movement (motor symptoms). Typical
other symptoms include disorders of mood, behavior, thinking,
and sensation (non-motor symptoms). Patients' individual symptoms
may be quite dissimilar and progression of the disease is
also distinctly individual. Parvo
virus-PCR
Parvovirus, commonly abbreviated to parvo,
is a genus of the Parvoviridae family linear, non-segmented
single stranded DNA viruses with an average genome size of
5 kbp. Parvoviruses are some of the smallest viruses found
in nature (hence the name, from Latin parvus meaning small).
Some have been found as small as 23nm.
Many types of mammalian species have a strain of parvovirus
associated with them. Parvoviruses tend to be specific about
the taxon of animal they will infect, but this is a somewhat
flexible characteristic. Thus, all strains of canine parvovirus
will affect dogs, wolves, and foxes, but only some of them
will infect cats.
No members of the genus Parvovirus are currently known to
infect humans, but humans can be infected by viruses from
three other genera from the Family Parvoviridae. These are
the Dependoviruses (e.g. Adeno-Associated Virus), the Erythroviruses
(e.g. Parvovirus B19) and the Bocaviruses.
Parvoviruses can cause disease in some animals. Fifth disease
is one of several possible manifestations of infection by
parvovirus B19.The disease is also referred to as erythema
infectiosum (meaning infectious redness) and as slapped cheek
syndrome, slapcheek, slap face or slapped face. In Japan the
disease is called 'apple sickness or ringo-byou' in reference
to the symptom of facial redness. The name "fifth disease"
derives from its historical classification as the fifth of
the classical childhood skin rashes or exanthems.
Pelizaeus Merzbacher
deletion/duplication
Pelizaeus-Merzbacher disease is an inherited
condition involving the brain and spinal cord (central nervous
system). This disease is one of a group of genetic disorders
called leukodystrophies. Leukodystrophies are characterized
by degeneration of myelin, which is the covering that protects
nerves and promotes the efficient transmission of nerve impulses.
Pelizaeus-Merzbacher disease is caused by an inability to
form myelin (dysmyelination). As a result, individuals with
this condition have impaired intellectual functions, such
as language and memory, and delayed motor skills, such as
coordination and walking. Typically, motor skills are more
severely affected than intellectual function; motor skills
development tends to occur more slowly and usually stops in
the second decade of life, followed by gradual deterioration.
Pelizaeus-Merzbacher disease is divided into classic and connatal
types. Although these two types differ in severity, their
features can overlap.
Classic Pelizaeus-Merzbacher disease is the more common type.
Within the first year of life, those affected with classic
Pelizaeus-Merzbacher disease typically experience weak muscle
tone (hypotonia), involuntary movements of the eyes (nystagmus),
and delayed development of motor skills such as crawling or
walking. As the child gets older, nystagmus usually stops
but other movement disorders develop, including muscle stiffness
(spasticity), problems with movement and balance (ataxia),
and involuntary jerking (choreiform movements).
Connatal Pelizaeus-Merzbacher disease is the more severe of
the two types. Symptoms can begin in infancy and include problems
feeding, a whistling sound when breathing, progressive spasticity
leading to joint deformities (contractures) that restrict
movement, speech difficulties (dysarthria), ataxia, and seizures.
Those affected with connatal Pelizaeus-Merzbacher disease
show little development of motor skills and intellectual function.
Mutations in the PLP1 gene cause Pelizaeus-Merzbacher disease.
Polycystic
Kidney dis (Aut. Rec. ARPKD) PND by linkage
Polycystic kidney disease (PKD, also known
as polycystic kidney syndrome) is a progressive, ciliopathic,
genetic disorder of the kidneys. It occurs in humans and other
organisms. PKD is characterized by the presence of multiple
cysts (hence, "polycystic") in both kidneys. The
disease can also damage the liver, pancreas, and rarely, the
heart and brain. The two major forms of polycystic kidney
disease are distinguished by their patterns of inheritance.
Autosomal dominant polycystic kidney disease (ADPKD) is generally
a late-onset disorder characterized by progressive cyst development
and bilaterally enlarged kidneys with multiple cysts. Kidney
manifestations in this disorder include renal function abnormalities,
hypertension, renal pain, and renal insufficiency. Approximately
50% of patients with ADPKD have end-stage renal disease (ESRD)
by the age of 60. ADPKD is a systemic disease with cysts in
other organs such as the liver (which may lead to cirrhosis),
seminal vesicles, pancreas, and arachnoid mater and non-cystic
abnormalities such as intracranial aneurysms and dolichoectasias,
dilation of the aortic root and dissection of the thoracic
aorta, mitral valve prolapse, and abdominal wall hernias.
Initial simian and human symptoms are hypertension, fatigue,
and mild to severe back or flank pain and urinary tract infections.
The disease often leads to chronic renal failure and may result
in total loss of kidney function, known as end stage renal
disease (ESRD), which requires some form of renal replacement
therapy (e.g. dialysis).
Autosomal recessive polycystic kidney disease (ARPKD) is much
rarer than ADPKD and is often fatal in utero or during the
first month of life. The signs and symptoms of the condition
are usually apparent at birth or in early infancy.
Porphyria- Acute intermittent
Common Mutation
Porphyria is a group of disorders caused
by abnormalities in the chemical steps that lead to heme production.
Heme is a vital molecule for all of the body's organs. It
is found mostly in the blood, bone marrow, and liver. Heme
is a component of hemoglobin, the molecule that carries oxygen
in the blood.
The major types of porphyria are each caused by mutations
in one of the genes required for heme production. Forms of
porphyria include ALAD deficiency porphyria, acute intermittent
porphyria, congenital erythropoietic porphyria, erythropoietic
protoporphyria, hepatoerythropoietic porphyria, hereditary
coproporphyria, porphyria cutanea tarda, and variegate porphyria.
In addition to the genetic forms of porphyria, some cases
of this disorder are caused by nongenetic factors such as
infections or exposure to certain prescription drugs. These
cases are described as sporadic or acquired porphyria.
The signs and symptoms of porphyria vary among the types.
Some types of porphyria (called cutaneous porphyrias) cause
the skin to become overly sensitive to sunlight. Areas of
the skin exposed to the sun are fragile and easily damaged.
Exposed skin may develop redness, blistering, infections,
scarring, changes in pigmentation, and increased hair growth.
Cutaneous porphyrias include congenital erythropoietic porphyria,
erythropoietic protoporphyria, hepatoerythropoietic porphyria,
and porphyria cutanea tarda.
Other types of porphyria (called acute porphyrias) mostly
affect the nervous system. Appearing quickly and lasting from
days to weeks, acute signs and symptoms include abdominal
pain, vomiting, constipation, and diarrhea. During an attack,
a person may also experience muscle weakness, seizures, fever,
loss of sensation, and mental changes such as anxiety and
hallucinations. These symptoms can be life-threatening in
rare cases, especially if the muscles that control breathing
become paralyzed. Acute porphyrias include acute intermittent
porphyria and ALAD deficiency porphyria. Two other forms of
porphyria, hereditary coproporphyria and variegate porphyria,
have a combination of acute symptoms and symptoms that affect
the skin.
Additional medical problems associated with some types of
porphyria include a low number of red blood cells (anemia),
enlargement of the spleen, abnormal liver function, and an
increased risk of developing liver cancer.
Some people with the genetic changes that cause porphyria,
particularly the acute forms of porphyria, never experience
any features of this condition. Environmental factors can
strongly influence the occurrence and severity of signs and
symptoms in some types of porphyria. Alcohol, smoking, certain
drugs, hormones, exposure to sunlight, other illnesses, stress,
and dieting or periods without food (fasting) can all trigger
the signs and symptoms of these disorders.
Mutations in the ALAD, CPOX, FECH, HMBS, PPOX, UROD, and UROS
genes cause porphyria.
The genes related to porphyria provide instructions for making
the enzymes needed to produce heme. Mutations in any of these
genes reduce enzyme activity, which limits the amount of heme
the body can produce. In some forms of porphyria, nongenetic
factors (such as certain drugs) also increase the demand for
heme and the enzymes required to make heme. The combination
of increased demand for this molecule and reduced enzyme activity
disrupts heme production. As a result, byproducts of the process
(compounds called porphyrins and porphyrin precursors) build
up in the body's tissues. When these toxic substances accumulate
in the skin and interact with sunlight, they cause the cutaneous
forms of porphyria. The acute forms of the disease occur when
porphyrins and porphyrin precursors build up and damage the
nervous system and other organs.
Porphyria- Sequencing of Porphobilinogen
gene
Prader Willi Syndrome-methylation
test
Prenatal diagnosis employs a variety of
techniques to determine the health and condition of an unborn
fetus. Without knowledge gained by prenatal diagnosis, there
could be an untoward outcome for the fetus or the mother or
both. Congenital anomalies account for 20 to 25% of perinatal
deaths. Specifically, prenatal diagnosis is helpful for:
• Managing the remaining weeks of the pregnancy
• Determining the outcome of the pregnancy
• Planning for possible complications with the birth
process • Planning for problems that may occur
in the newborn infant • Deciding whether to continue
the pregnancy • Finding conditions that may affect
future pregnancies
For dominant disorders, testing of a positive control is an
essential aspect of accurate prenatal diagnosis. Separate
Carrier Tests on the parents are optional. During prenatal
diagnosis, we must have on hand a specimen from an affected
family member and a maternal specimen for MCC testing. If
such specimens were tested more than 6 months previously,
fresh specimens are requested from the mother and (if he is
a positive control) the father.
Prothrombin gene polymorphism (G20210A)
Inherited thrombophilia is a genetic tendency
to venous thromboembolism. Factor V Leiden is the most common
cause of the syndrome accounting for 40 to 50 percent of cases.
The prothrombin gene mutation and deficiencies in protein
S, protein C, and antithrombin account for most of the remaining
cases, while rare causes include the dysfibrinogenemias.
The total incidence of an inherited thrombophilia in subjects
with a deep vein thrombosis ranges from 24 to 37 percent overall
compared to about 10 percent in controls.
PROTHROMBIN GENE — Prothrombin (factor II) is the precursor
of thrombin, the end-product of the coagulation cascade. It
is a vitamin K-dependent protein which is synthesized in the
liver and circulates with a half-life of approximately three
to five days. Vitamin K acts as a cofactor for posttranslational
gamma-carboxylation of prothrombin which is required for functional
activity.
Prothrombin G20210A — The human prothrombin gene spans
21 kb on chromosome 11p11-q12 and consists of 14 exons and
13 introns, which account for 90 percent of the sequence.
A report published in 1996 identified a transition (guanine
to adenine) at nucleotide 20210 in the 3' untranslated region
of the prothrombin gene as a risk factor for thrombosis. Heterozygous
carriers have 30 percent higher plasma prothrombin levels
than normals. Restrictive
Dermopathy (Specific mutation by sequencing)
This is a rare inherited disorder characterized
by abnormally tight noncompliant skin. Patients have flexion
contractures of the extremities, low set malformed ears, micrognathia,
hypertelorism, and a small fixed open mouth. Abnormalities
of the hair and nails, linear skin splits, and ectropion are
variably present.
Restrictive dermopathy (RD) is caused by the loss of the gene
ZMPSTE24, which encodes a protein responsible for the cleavage
of farnesylated prelamin A (progerin) into mature non-farnesylated
lamin. This results in the accumulation of farnesyl-prelamin
A at the nuclear membrane. Mechanistically, restrictive dermopathy
is somewhat similar to Hutchinson-Gilford progeria syndrome
(HGPS), a disease where the last step in lamin processing
is hindered by a mutation that causes the loss of the ZMPSTE24
cleavage site in the lamin A gene.
Retinoblastoma- deletion/duplication
Retinoblastoma is a cancer of the retina. Development of
this tumor is initiated by mutations that inactivate both
copies of the RB1 gene, which codes for the retinoblastoma
protein.
It is a cancer of one or both eyes which occurs in young
children. There are approximately 350 new diagnosed cases
per year in the United States. Retinoblastoma affects one
in every 15,000 to 30,000 live babies that are born in the
United States. Retinoblastoma affects children of all races
and both boys and girls.
The retinoblastoma tumor(s) originate in the retina, the
light sensitive layer of the eye which enables the eye to
see. When the tumors are present in one eye, it is referred
to as unilateral retinoblastoma, and when it occurs in both
eyes it is referred to as bilateral retinoblastoma. Most
cases (75%) involve only one eye (unilateral); the rest
(25%) affect both eyes (bilateral). The majority (90%) of
retinoblastoma patients have no family history of the disease;
only a small percentage of newly diagnosed patients have
other family members with retinoblastoma (10%).
Prenatal diagnosis can be done with the CVS samples.
Rett Syndrome MECP2 deletion/ duplication
Rett syndrome (also called Rett disorder) is a neurodevelopmental
disorder that is classified as a pervasive developmental disorder
by the DSM-IV. The clinical features include a deceleration
of the rate of head growth (including microcephaly in some)
and small hands and feet. Stereotypic, repetitive hand movements
such as mouthing or wringing are also noted. Symptoms of the
disorder include cognitive impairment and problems with socialization,
the latter during the regression period. Socialization typically
improves by the time they enter school. Girls with Rett syndrome
are very prone to gastrointestinal disorders and up to 80%
have seizures.They typically have no verbal skills, and about
50% of females are not ambulatory. Scoliosis, growth failure,
and constipation are very common and can be problematic. Man
argue that it is misclassified as a pervasive developmental
disorder, just as it would be to include such disorders as
fragile X syndrome, tuberous sclerosis, or Down syndrome where
one can see autistic features. The symptoms of this disorder
are most easily confused with those of Angelman syndrome,
cerebral palsy and autism. Rett
Syndrome MECP2 -Sequencing
Blood typing is especially important during pregnancy. If
the mother is found to be Rh-, the father should also be tested.
If the father has Rh+ blood, the mother needs to receive a
treatment to help prevent the development of substances that
may harm the unborn baby. See: Rh incompatibility
If you are Rh+, you can receive Rh+ or Rh- blood. If you are
Rh-, you can only receive Rh- blood. If your blood cells stick
together when mixed with: • Anti-A serum, you have
type A blood • Anti-B serum, you have type B blood
• Both anti-A and anti-B serums, you have type
AB blood RH typing: •
If your blood cells stick together when mixed with anti-Rh
serum, you have type Rh-positive blood. • If your
blood does not clot when mixed with anti-Rh serum, you have
type Rh-negative blood. Risks associated
with taking blood may include: • Fainting
or feeling light-headed • Multiple punctures to
locate veins • Excessive bleeding •
Hematoma (blood accumulating under the skin) •
Infection (a slight risk any time the skin is broken)
Rh incompatibility is a condition that develops when a pregnant
woman has Rh-negative blood and the baby in her womb has Rh-positive
blood. During pregnancy, red blood cells from the fetus can
get into the mother's bloodstream as she nourishes her child
through the placenta. If the mother is Rh-negative, her system
cannot tolerate the presence of Rh-positive red blood cells.
In such cases, the mother's immune system treats the Rh-positive
fetal cells as if they were a foreign substance and makes
antibodies against the fetal blood cells. These anti-Rh antibodies
may cross the placenta into the fetus, where they destroy
the fetus's circulating red blood cells.
First-born infants are often not affected -- unless the mother
has had previous miscarriages or abortions, which could have
sensitized her system -- as it takes time for the mother to
develop antibodies against the fetal blood. However, second
children who are also Rh-positive may be harmed.
Hemoglobin changes into bilirubin, which causes an infant
to become yellow (jaundiced). The jaundice of Rh incompatibility,
measured by the level of bilirubin in the infant's bloodstream,
may range from mild to dangerously high levels of bilirubin.
Rh incompatibility develops only when the mother is Rh-negative
and the infant is Rh-positive. Special immune globulins, called
RhoGAM, are now used to prevent this sensitization. In developed
countries such as the US, hydrops fetalis and kernicterus
have decreased markedly in frequency as a result of these
preventive measures.
Rh incompatibility can cause symptoms ranging from very mild
to fatal. In its mildest form, Rh incompatibility causes destruction
of red blood cells. Symptoms may include:
" Jaundice " Hypotonia " Motormental retardation
" Polyhydramnios (before birth)
Rubella (PCR)
Rubella, commonly known as German measles, is a disease caused
by Rubella virus. The name is derived from the Latin, meaning
little red. Rubella is also known as German measles because
the disease was first described by German physicians in the
mid-eighteenth century. This disease is often mild and attacks
often pass unnoticed. The disease can last one to five days.
Children recover more quickly than adults. Infection of the
mother by Rubella virus during pregnancy can be serious; if
the mother is infected within the first 20 weeks of pregnancy,
the child may be born with congenital rubella syndrome (CRS),
which entails a range of serious incurable illnesses. Spontaneous
abortion occurs in up to 20% of cases.
Rubella is a common childhood infection usually with minimal
systemic upset although transient arthropathy may occur in
adults. Serious complications are very rare. Apart from the
effects of transplacental infection on the developing foetus,
rubella is a relatively trivial infection.
Acquired, (i.e. not congenital), rubella is transmitted via
airborne droplet emission from the upper respiratory tract
of active cases. The virus may also be present in the urine,
faeces and on the skin. There is no carrier state: the reservoir
exists entirely in active human cases. The disease has an
incubation period of 2 to 3 weeks.
In most people the virus is rapidly eliminated. However, it
may persist for some months post partum in infants surviving
the CRS. These children are a significant source of infection
to other infants and, more importantly, to pregnant female
contacts. Russel
Silver Syndrome (UP Disomy)
Silver-Russell dwarfism, also called Silver-Russell syndrome
(SRS) or Russell-Silver syndrome (RSS) is a growth disorder
occurring in approximately 1/75000 births. In the United States
it is usually referred to as Russel-Silver Syndrome, and Silver-Russell
Syndrome elsewhere. It is one of 200 types of dwarfism and
one of five types of primordial dwarfism and is one of the
few forms that is considered treatable. Its exact cause is
unknown, but present research points toward a genetic component,
possibly following maternal genes. There is no statistical
significance of the syndrome occurring in males or females.
Spinal Muscular
atrophy, diagnosis
Spinal Muscular Atrophy (SMA) is a term applied to a number
of different disorders, all having in common a genetic cause
and the manifestation of weakness due to loss of the motor
neurons of the spinal cord and brainstem. Infantile
SMA is the most severe form. Some of the symptoms include:
• muscle weakness • poor muscle tone
• weak cry • limpness or a tendency to flop
• difficulty sucking or swallowing •
accumulation of secretions in the lungs or throat •
legs that tend to be weaker than the arms • hypotonia,
areflexia, and multiple congenital contractures (arthrogryposis)
associated with loss of anterior horn cells • feeding
difficulties • increased susceptibility to respiratory
tract infections • developmental milestones, such
as lifting the head or sitting up, can't be reached.
In general, the earlier the symptoms appear, the shorter the
life span. The onset is sudden and dramatic. Once symptoms
appear the motor neuron cells quickly deteriorate shortly
after. The disease can be fatal and there is no cure for SMA
yet known. The major management issue in Type 1 SMA is the
prevention and early treatment of respiratory infections;
pneumonia is the cause of death in the majority of the cases.
Infants with Type 1 SMA have a life expectancy of less than
two years, however, some grow to be adults. Intellectual and
later, sexual functions, are unaffected by SMA.
Spino- Cerebellar
ataxia -One type
Spinocerebellar ataxia (SCA) is a genetic disease with multiple
types, each of which could be considered a disease in its
own right.
Spinocerebellar ataxia (SCA) is one of a group of genetic
disorders characterized by slowly progressive incoordination
of gait and often associated with poor coordination of hands,
speech, and eye movements. Frequently, atrophy of the cerebellum
occurs.
As with other forms of ataxia, SCA results in unsteady and
clumsy motion of the body due to a failure of the fine coordination
of muscle movements, along with other symptoms.
The symptoms of the condition vary with the specific type
(there are several), and with the individual patient. Generally,
a person with ataxia retains full mental capacity but may
progressively lose physical control.
Type 1 patients suffer from Hypermetric saccades, slow saccades,
upper motor neuron (note: saccades relates to eye movement)
Spino- Cerebellar
ataxia -Two type
Spinocerebellar ataxia (SCA) is a genetic disease with multiple
types, each of which could be considered a disease in its
own right.
Spinocerebellar ataxia (SCA) is one of a group of genetic
disorders characterized by slowly progressive incoordination
of gait and often associated with poor coordination of hands,
speech, and eye movements. Frequently, atrophy of the cerebellum
occurs.
As with other forms of ataxia, SCA results in unsteady and
clumsy motion of the body due to a failure of the fine coordination
of muscle movements, along with other symptoms.
The symptoms of the condition vary with the specific type
(there are several), and with the individual patient. Generally,
a person with ataxia retains full mental capacity but may
progressively lose physical control.
Type 2 patients suffer from Diminished velocity saccades areflexia
(absence of neurologic reflexes)
Spino- Cerebellar ataxia -package (1,2,3,6,7,8,12,
17 DRPLA)
Spinocerebellar ataxia (SCA) is one of a group of genetic
disorders characterized by slowly progressive incoordination
of gait and often associated with poor coordination of hands,
speech, and eye movements. Frequently, atrophy of the cerebellum
occurs.
As with other forms of ataxia, SCA results in unsteady and
clumsy motion of the body due to a failure of the fine coordination
of muscle movements, along with other symptoms. The symptoms
of the condition vary with the specific type (there are several),
and with the individual patient. Generally, a person with
ataxia retains full mental capacity but may progressively
lose physical control.
This is the package identification of various kinds of SCA.
Spinal bulbar
muscular atrophy (SBMA) CAG repeats
Spinal bulbar muscular atrophy is a genetic disease in which
loss of nerve cells in the spinal cord and brainstem called
motor neurons affects the part of the nervous system that
controls voluntary muscle movement.
The cause is a genetic mutation that affects an X-chromosome
gene for the androgen receptor protein, apparently making
it toxic to nerve cells.
Onset of the disease is in Adulthood - 30 to 50 years.
Symptoms include, weakness of the muscles of the mouth, throat,
face and limbs. Symptoms related to abnormal processing of
androgens (male hormones), such as breast enlargement and
reduced fertility, may also occur.
Spondyloepiphyseal dysplasia X-linked gene
sequencing
Spondyloepiphyseal dysplasia congenita (abbreviated to SED
more often than SDC) is a rare disorder of bone growth that
results in dwarfism, characteristic skeletal abnormalities,
and occasionally problems with vision and hearing. The name
of the condition indicates that it affects the bones of the
spine (spondylo-) and the ends of bones (epiphyses), and that
it is present from birth (congenital). The signs and symptoms
of spondyloepiphyseal dysplasia congenita are similar to,
but milder than, the related skeletal disorders achondrogenesis
type 2 and hypochondrogenesis. Spondyloepiphyseal dysplasia
congenita is a subtype of collagenopathy, types II and XI.
Sry+Amxy gene
study (Y chromosome)
Thalassemia-beta (Confirmation of known
mutation)
Thalassemia is an inherited autosomal recessive blood disease.
In thalassemia, the genetic defect results in reduced rate
of synthesis of one of the globin chains that make up hemoglobin.
Reduced synthesis of one of the globin chains causes the formation
of abnormal hemoglobin molecules, and this in turn causes
the anemia which is the characteristic presenting symptom
of the thalassemias.
Hemoglobinopathies imply structural abnormalities in the globin
proteins themselves. The two conditions may overlap, however,
since some conditions which cause abnormalities in globin
proteins (hemoglobinopathy) also affect their production (thalassemia).
Thus, some thalassemias are hemoglobinopathies, but most are
not.
Generally, thalassemias are prevalent in populations that
evolved in humid climates where malaria was endemic, but affects
all races. Thalassemias are particularly associated with Arab-Americans,
people of Mediterranean origin, and Asians. The estimated
prevalence is 16% in people from Cyprus, 3-14% in Thailand,
and 3-8% in populations from India, Pakistan, Bangladesh,
Malaysia and China. There are also prevalences in descendants
of people from Latin America, and Mediterranean countries
(e.g. Spain, Portugal, Italy, Greece and others). A very low
prevalence has been reported from people in Africa (0.9%),
with those in northern Africa having the highest prevalence,
and northern Europe (0.1%).
The thalassemias are classified according to which chain of
the hemoglobin molecule is affected (see hemoglobin for a
description of the chains). In a thalassemias, production
of the a globin chain is affected, while in ß thalassemia
production of the ß globin chain is affected.
Thalassemia produces a deficiency of a or ß globin,
unlike sickle-cell disease which produces a specific mutant
form of ß globin.
Deletion of one of the a loci has a high prevalence in people
of African-American or Asian descent, making them more likely
to develop a thalassemias. ß thalassemias are common
in African-Americans, but also in Greeks and Italians.
Alpha (a) thalassemias
The a thalassemias involve the genes HBA1 (Online 'Mendelian
Inheritance in Man' (OMIM) 141800) and HBA2 (Online 'Mendelian
Inheritance in Man' (OMIM) 141850), inherited in a Mendelian
recessive fashion. It is also connected to the deletion of
the 16p chromosome. a thalassemias result in decreased alpha-globin
production, therefore fewer alpha-globin chains are produced,
resulting in an excess of ß chains in adults and excess
? chains in newborns. The excess ß chains form unstable
tetramers (called Hemoglobin H or HbH of 4 beta chains) which
have abnormal oxygen dissociation curves. Beta
(ß) thalassemias
Beta thalassemias are due to mutations in the HBB gene on
chromosome 11 (Online 'Mendelian Inheritance in Man' (OMIM)
141900), also inherited in an autosomal-recessive fashion.
The severity of the disease depends on the nature of the mutation.
Mutations are characterized as (ßo) if they prevent
any formation of ß chains; they are characterized as
(ß+) if they allow some ß chain formation to occur.
In either case there is a relative excess of a chains, but
these do not form tetramers: rather, they bind to the red
blood cell membranes, producing membrane damage, and at high
concentrations they form toxic aggregates. Delta
(d) thalassemia
As well as alpha and beta chains being present in hemoglobin
about 3% of adult hemoglobin is made of alpha and delta chains.
Just as with beta thalassemia, mutations can occur which affect
the ability of this gene to produce delta chains.
There are an estimated 60-80 million people in the world who
carry the beta thalassemia trait alone. This is a very rough
estimate and the actual number of thalassemia Major patients
is unknown due to the prevalence of thalassemia in less developed
countries in the Middle East and Asia.
Thanotrophic
dwarfism (common mutation)
Thrombophilia Profile-
3 genes- MTHFR, Factor v Leiden, Prothrombin
Thrombophilia, or hypercoagulability, means an increased risk
for thrombosis. Thrombophilia may be congenital or acquired.
Thrombosis may be cardiovascular, including angina, myocardial
infarction (MI), and peripheral vascular disease (PVD); cerebrovascular,
including transient ischemic attack (TIA) and stroke, or venous
thromboembolic disease, including deep venous thrombosis (DVT)
or pulmonary embolism (PE). Cardiovascular and cerebrovascular
diseases are highly dependent on platelet aggregation while
venous thromboembolic diseases may be related to coagulation
system abnormalities. Factors involved in
the Thrombophillic profiles. • APCR: heterozygous
factor V Leiden mutation • APCR: homozygous factor
V Leiden mutation • Prothrombin G20210A heterozygotes
• Antithrombin deficiency heterozygotes •
Protein C deficiency heterozygotes • Protein S deficiency
heterozygotes Toxoplasmosis
(PCR)
Toxoplasmosis is a parasitic disease caused by the protozoan
Toxoplasma gondii.[1] The parasite infects most warm-blooded
animals, including humans, but the primary host is the felid
(cat) family. Animals are infected by eating infected meat,
by ingestion of faeces of a cat that has itself recently been
infected, or by transmission from mother to fetus. Cats have
been shown as a major reservoir of this infection.
Up to one third of the world's population is estimated to
carry a Toxoplasma infection.[3] The Centers for Disease Control
and Prevention notes that overall seroprevalence in the United
States as determined with specimens collected by the National
Health and Nutritional Assessment Survey (NHANES) between
1999 and 2004 was found to be 10.8%, with seroprevalence among
women of childbearing age (15 to 44 years) of 11%.
During the first few weeks, the infection typically causes
a mild flu-like illness or no illness. After the first few
weeks of infection have passed, the parasite rarely causes
any symptoms in otherwise healthy adults. However, people
with a weakened immune system, such as those infected with
HIV or pregnant, may become seriously ill, and it can occasionally
be fatal. The parasite can cause encephalitis (inflammation
of the brain) and neurologic diseases and can affect the heart,
liver, and eyes (chorioretinitis).
Waardenburg Syndrome Pax 3 gene sequencing
Waardenburg syndrome is a rare genetic disorder most often
characterized by varying degrees of deafness, minor defects
in structures arising from the neural crest, and pigmentation
anomalies.
This condition is usually inherited in an autosomal dominant
pattern, which means one copy of the altered gene is sufficient
to cause the disorder. In most cases, an affected person has
one parent with the condition. A small percentage of cases
result from new mutations in the gene; these cases occur in
people with no history of the disorder in their family.
Some cases of type II and type IV Waardenburg syndrome appear
to have an autosomal recessive pattern of inheritance, which
means two copies of the gene must be altered for a person
to be affected by the disorder. Most often, the parents of
a child with an autosomal recessive disorder are not affected
but are carriers of one copy of the altered gene.
Types I and II are the most common types of the syndrome,
whereas types III and IV are rare. Overall, the syndrome affects
perhaps 1 in 42,000 people. About 1 in 30 students in schools
for the deaf have Waardenburg syndrome. All races and both
sexes are affected equally. The highly variable presentation
of the syndrome makes it difficult to arrive at precise figures
for its prevalence. Symptoms vary from one
type of the syndrome to another and from one patient to another,
but they include: • Very pale or brilliantly
blue eyes, eyes of two different colors (complete heterochromia),
or eyes with one iris having two different colours (sectoral
heterochromia); • A forelock of white hair (poliosis),
or premature graying of the hair; • Wide-set eyes
(hypertelorism) due to a prominent, broad nasal root (dystopia
canthorum—particularly associated with type I);
• Moderate to profound hearing impairment (higher frequency
associated with type II); and • A low hairline
and eyebrows that touch in the middle. • Patches
of white pigmentation on the skin have been observed in some
people. Sometimes, abnormalities of the arms, associated with
type III, have been observed. • Type IV may include
neurologic manifestations.
Waardenburg syndrome has also been associated with a variety
of other congenital disorders, such as intestinal and spinal
defects, elevation of the scapula, and cleft lip and palate.
Wilson
diseases-PND by linkage
Wilson's disease or hepatolenticular degeneration is an autosomal
recessive genetic disorder in which copper accumulates in
tissues; this manifests as neurological or psychiatric symptoms
and liver disease. It is treated with medication that reduces
copper absorption or removes the excess copper from the body,
but occasionally a liver transplant is required.
The condition is due to mutations in the Wilson disease protein
(ATP7B) gene. A single abnormal copy of the gene is present
in 1 in 100 people, who do not develop any symptoms (they
are carriers). If a child inherits the gene from both parents,
they may develop Wilson's disease. Symptoms usually appear
between the ages of 6 and 20 years, but cases in much older
patients have been described. Wilson's disease occurs in 1
to 4 per 100,000 people. Wilson's disease is named after Dr
Samuel Alexander Kinnier Wilson (1878-1937), the British neurologist
who first described the condition in 1912.
UGT1A1 * 28 Genotyping
This gene encodes a UDP-glucuronosyltransferase, an enzyme
of the glucuronidation pathway that transforms small lipophilic
molecules, such as steroids, bilirubin, hormones, and drugs,
into water-soluble, excretable metabolites. This gene is part
of a complex locus that encodes several UDP-glucuronosyltransferases.
The locus includes thirteen unique alternate first exons followed
by four common exons. Four of the alternate first exons are
considered pseudogenes. Each of the remaining nine 5' exons
may be spliced to the four common exons, resulting in nine
proteins with different N-termini and identical C-termini.
Each first exon encodes the substrate binding site, and is
regulated by its own promoter. Mutations in this gene result
in Crigler-Najjar syndromes types I and II and in Gilbert
syndrome.
Lack of expression of UGT1A1 in the neonatal liver is the
major cause of jaundice in newborns. This jaundice is generally
caused by the natural breakdown of fetal blood cells which
produces bilirubin that cannot be cleared if UGT1A1 is expressed
at low levels or is absent. This type of jaundice can remedied
by UV light exposure. X-linked
ichthyosis (Deletion in STS gene)
X-linked ichthyosis (XLI) is a skin condition caused by the
hereditary deficiency of the steroid sulfatase (STS) enzyme
that affects 1 in 2000 to 1 in 6000 males. XLI manifests with
dry, scaly skin and is due to deletions or mutations in the
STS gene. XLI and can also occur in the context of larger
deletions causing contiguous gene syndromes. Treatment is
largely aimed at alleviating the skin symptoms.
The major symptoms of XLI include scaling of the skin, particularly
on the neck, trunk, and lower extremities. The extensor surfaces
are typically the most severely affected areas. The >4
mm diameter scales adhere to the underlying skin and can be
dark brown or gray in color. Symptoms may subside during the
summer. X-linked
hydrocephalus- MASA syndrome-linkage
A rare genetic disorder characterized by hydrocephalus, short
flexed thumbs and mental deficiency. Symptoms include
• Mental deficiency • Spasticity •
Narrow scaphocephalic cranium • Hydrocephalus
• Thumb flexed over palm
XMN Polymorphism Gr gene (thalassemia child)
Y-Chromosome deletions
(10)
Male infertility affects approximately 2-7% of couples around
the world. Over one in ten men who seek help at infertility
clinics are diagnosed as severely oligospermic or azoospermic.
Recent extensive molecular studies have revealed that deletions
in the azoospermia factor region of the long arm of the Y
chromosome are associated with severe spermatogenic impairment
(absent or severely reduced germ cell development). Genetic
research into male infertility, in the last 7 years, has resulted
in the isolation of a great number of genes or gene families
on the Y chromosome, some of which are believed to influence
spermatogenesis. |