| deCODE T2 TM is a DNA-based
test designed to help individuals, working with their
doctor, better understand their risk of type 2 diabetes
(T2D) and to enable more effective prevention strategies.
It defines genetic risk for T2D, independent of family
history and obesity, that ranges from 0.6 to 2 fold
the general population risk.
Understanding risk can empower prevention. By knowing
and understanding genetic risk, it may be possible to
take actions that reduce or minimize the likelihood
of an individual developing diabetes. In addition to
predicting or recalculating the remaining lifetime risk
of developing T2D, the test results can predict the
likelihood of prediabetes coverting to the full blown
T2D and which patients may benefit the most from preventive
management.
Type 2 diabetes is a chronic condition that develops
when the body either becomes resistant to or doesn’t
secrete enough insulin.
deCODE T2 is a test to detect versions of SNPs (single
nucleotide polymorphism), a one letter variations in
the sequence of the genome, that predict
- the risk of developing T2D
- the risk of converting from prediabetes (impaired
fasting blood sugar and glucose tolerance test) to
full blown T2D
- who are candidates for the most aggressive preventive
measures
- what medication may be most effective for treatment
deCODE T2TM is a risk assessment test but not a determinate
test about who will or will not get T2D or respond or
not respond to preventive measures or treatment.
Knowing one's increased risk of developing T2D according
to the deCODE T2 TM results should act as motivation for
individuals to be more compliant with suggested life style
changes and weight loss recommendations by their physicians.
For patients who fail to lose significant weight within
6 months, high risk prediabetics may benefit the most
from nutritional advice and more aggressive lifestyle
intervention. Finally, high risk prediabetics who still
fail to respond to lifestyle intervention, may be prime
candidates for metformin as suggested by the latest ADA
recommendations (Standards of medical care in diabetes--2008.
Diabetes Care, 2008. 31 Suppl 1: S12-54). You may wish
to consult with your physician regarding specific alternatives
for high risk prediabetics.
deCODE MI™ is a DNA-based test for assessing an
inherited risk factor for myocardial infarction (MI).
The test detects versions of SNPs (single nucleotide polymorphism)
– single letter variations in the sequence of the
genome – in a region of the genome that deCODE has
linked to increased risk of MI.
The medical term for heart attack is myocardial infarction.
A heart attack is also sometimes called a coronary artery
thrombosis or coronary artery occlusion.
Common diseases such as MI occur at the interface of genes
and the environment, as both inherited as well as lifestyle
and other health risk factors play important roles in
the disease process. As a result, it is important to understand
what carrying an inherited risk variant for a common disease
means, and how that information can help to keep a predisposition
to a given condition from ever developing into a disease.The
deCODE MI™ test detects versions of SNPs (single
nucleotide polymorphism) – single letter variations
in the sequence of the genome – in a region of the
genome that deCODE has linked to increased risk of MI.
The conventional risk factors for MI and other atherosclerotic
diseases include high serum total cholesterol levels,
elevated serum LDL cholesterol, and low serum HDL cholesterol,
cigarette smoking, diabetes, hypertension, and obesity.
Despite increased knowledge of the specific risk factors
and the wide-spread use of medications that inhibit thrombosis
(aspirin) or treat medical risk factors, such as elevated
cholesterol levels in blood (statins), diabetes or hypertension,
the prevalence of atherosclerotic disease continues to
be high. This is largely attributed to the aging of the
population and the increase in the prevalence of modifiable
risk factors in large segments of the population.
The deCODE Glaucoma™ test detects versions of
SNPs (single nucleotide polymorphism) – single
letter variations in the sequence of the genome –
in a specific gene that deCODE has linked to increased
risk of one of the more common types of glaucoma, exfoliation
type glaucoma.
The medical term “Glaucoma” refers to a
group of eye diseases affecting the major nerve of vision,
called the optic nerve. The optic nerve receives light
from the retina and transmits impulses to the brain
perceived as vision. The symptoms of glaucoma present
as a result of a particular pattern of progressive damage
to the optic nerve that generally begins with a subtle
loss of side vision (peripheral vision). If glaucoma
is not diagnosed and treated, it can progress to loss
of central vision and blindness.
Common diseases such as glaucoma occur at the interface
of genes and the environment, as both inherited as well
as other health risk factors play important roles in
the disease process. As a result, it is important to
understand what carrying an inherited risk variant for
a common disease means, and how that information can
help to keep a predisposition to a given condition from
ever developing into a disease. deCODE Glaucoma™
is a reference laboratory DNA test for assessing an
inherited risk factor for exfoliation glaucoma.
The deCODE ProCa ™ test is a novel, non-invasive,
DNA-based test for the first genetic risk factors ever
found to confer risk for a common type of cancer in
the general population. These markers are not dependent
on a family history of prostate cancer – in fact,
they are independent of family history and the genetic
risk of the ProCa test multiples with the family risks
mentioned above. All but one of the variants were discovered
in Iceland and confirmed in several American and European
ancestry cohorts but have also been confirmed in several
other populations by independent research groups.
Prostate cancer is the most commonly diagnosed non-skin
cancer in men in developed countries and the second
leading cause of cancer death, after lung cancer, among
men in the United States. It carries a lifetime risk
of 16% and a mortality of 3% in the general population.
The risk is generally higher for men of African-American
heritage, for men with affected fathers and/or brothers,
and for those with relatives diagnosed at younger ages.
A family history of breast or ovarian cancer can also
be a risk factor, as the diseases share a common genetic
mutation.
Almost 95 percent of prostate cancers are adenocarcinomas,
cancers originating in the prostate´s gland cells.
Most prostate cancers grow very slowly, improving the
chances of early detection, diagnosis, treatment and
survivability. Early detection is the key to overcoming
prostate cancer; the five-year survival rate among men
whose prostate cancer is caught early is 100 percent.
The deCODE ProCa™ test identifies eight known
variants, three on chromosome 8 two on chromosome 17
one on chromosome 2 (in the 2p15 region), one on chromosome
11 and one on the X-chromosome (sex chromosome). Based
on the presumption that these markers are independent
of each other, and the individual risks therefore multiply,
the various genotype combinations have associated relative
risks in the range of 0.33to 17.6) compared to the general
population risk. Combined, these 8 variants appear to
account for about half of the cases of prostate cancer
(sometimes termed population attributable risk). About
40% of the population has a genotype combination of
the tested markers that have an increased relative risk
(>1) over the general population and about 10% of
the population has a genotype combinations that confer
an average two-fold relative risk, and about 1% have
relative risk above 3. One should be careful to apply
extreme risk results to individuals since they are based
on presumptions of a multiplicative model and are associated
with genotype combinations that are extremely rare.
Note that deCODE ProCa™ only measures these 8
validated genes. There are likely other genes that have
not yet been discovered and there are other risk factors
such as family history and ethnicity that need to be
multiplied to this genetic risk to refine an individual’s
risk.
The deCODE Breast CancerTM test is a novel, DNA-based
reference laboratory test for the first common genetic
risk factors to be identified that contribute to a substantial
proportion of female breast cancers in the general population.
The deCODE BreastCancerTM test determines whether the
subject has inherited the risk or non-risk version at
7 different variable sites in the human genome. By comparing
deCODE BreastCancer™ test results to the general
risk of women in the population it can be seen whether
the person tested has a risk greater or lower than the
average population risk. The risks at each of the 7 markers
are multiplied together to define combined risks from
0.4-to 4.0- fold the relative general population risk.
The deCODE BreastCancerTM test examines only genetic risk
factors, so other factors such as age and hormonal factors
need also to be taken into account. By combining the test
results and risks associated with other known risk factors,
a more complete lifetime risk estimate can be generated.
The test is done on the DNA isolated from an inner cheek
or a blood sample, and it looks at 7 marker variants (SNPs,
single nucleotide polymorphisms) in the genome that people
inherit from their parents and have been associated with
increased risk for breast cancer. These variations are
very common in the population but have been shown to affect
a woman’s risk of getting breast cancer. The test’s
validity in identifying risk for breast cancer has been
confirmed in a number of large, multinational studies
including more than 10,000 patients and 30,000 controls.
According to the test results, only about 5% of women
have an average 2-fold risk for breast cancer compared
to the general population, and about 1% have a 3-fold
risk. This translates for white women to a lifetime risk
of 24% and 36%, respectively, versus the average population-based
risk of 12%. It is estimated that these 7 markers together
account for 60% of breast cancer (population attributable
risk).
Breast cancers can be classified as either estrogen receptor
positive (ER+) or estrogen receptor negative (ER-), depending
on whether they contain certain proteins that allow the
cancer to respond to the female sex hormone estrogen,
which can make the breast tissues more susceptible to
hormonal risk factors and drive small tumors into larger
tumors. Several of the genetic variants examined by the
deCODE BreastCancerTM test affect the chance that a breast
tumor, if it arises, will be ER+ or ER-. At the same time,
ER+ tumors may be more amenable to prevention by drugs
that target the estrogen pathway, such as tamoxifen.
The deCODE BreastCancerTM test does not test for what
is generally referred to as familial or inherited forms
of breast cancer caused by rare mutations in breast cancer
genes such as BRCA1, BRCA2, TP53, and PTEN. These mutations
confer extremely high risks of breast cancer and occur
only in rare families that may have exceptionally high
numbers of breast cancer cases, often arising in younger
women and sometimes along with ovarian cancer. Mutations
in these genes need to be tested for separately under
the guidance of a genetic counselor. However, for individuals
who are known to carry mutations in these genes, the deCODE
BreastCancerTM test provides additional information on
their overall risk of breast cancer since some of the
test markers are shown to influence the effect of these
rare breast cancer gene mutations.
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