What is Genomics?
Genomics is the study of the DNA, Genes, and Chromosomes which make up the complete set of genetic instructions, the genome, contained within nearly every cell in your body. But, as with so many questions in science, this answer leads to new questions.

DNA
The best way to think of DNA is as a long molecule made of a chain of 4 smaller molecules called nucleotides, symbolized by the letters, A, T, C, and G. These letters store instructions on how to make proteins and ultimately, how to make you. Our DNA molecules are organized into a double helix structure which resembles a spiral staircase. However, with this staircase, there are certain rules that dictate which letters can sit across from each other on each step, rules which help in reading and replicating your DNA instructions. The rules strictly require that the letter “A” must be opposite the letter “T”, and the letter “G” opposite the letter “C”. In this way, it is possible to read one half of the “staircase” and know precisely what the other half should look like. In fact, this is the basic idea behind how your DNA is copied when your cells divide.

Genes
Genes are simply long sequences of DNA “letters” which provide instructions for making protein and proteins perform countless tasks within your cells, from providing structural support, to breaking down waste. It is the sequence of the DNA “letters” within each gene that affects the way the instructions are interpreted in terms of the proteins that are produced. This is analogous to the manner we interpret words on a page. For example, the same four letters are in the words, “mate” and “team,” but the sequence of the letters affects our interpretation of their meanings. On the other hand, sometimes a difference in a genetic sequence does not lead to a change in the protein. The analogy holds with words like, “color” and “colour” for example. These words have different spellings but are interpreted identically.

Chromosomes
As we move from DNA to Genes and from Genes to Chromosomes, we are basically zooming out from a highly magnified view of your DNA to a much wider view. Scientifically speaking, Chromosomes are extremely long interwoven and highly coiled pieces of DNA, the longest continuous pieces of DNA in our cells. But, if we carry the previous analogy of genes resembling words and sentences a little further, then it follows that chromosomes can be thought of as complete chapters in the story of you. They are composed of many words (genes), they have a clear beginning and ending, and to an extent they can stand alone as a discrete unit that tells part of the story of your life.

Genome
As we zoom further out from individual DNA molecules, past the chromosome level, we can see that we have multiple chromosomes, 46 to be exact (23 pairs), and the summation of these chromosomes make up what is considered to be your genome. You can then infer that your genome is composed of all your DNA, Genes, and Chromosomes and it follows that Genomics is the study of these three levels of genetic material. Going back to our analogy, you can think of your genome as being analogous to your complete autobiography. It consists of 23 chapters, albeit with two copies of each one, and it tells the complete story of you.

SNP's
SNP is short for Single Nucleotide Polymorphism and is pronounced “snip” but, it's not as complicated as it sounds. As previously mentioned, a nucleotide is simply one of the four letters of DNA, A, T, C, or G. The word Polymorphism is really just a fancy way of saying, “many forms”. Therefore, a single nucleotide polymorphism is just a single letter of DNA, in a specific location, that can take many forms, i.e. it can be an A, T, C, or G. SNP's are significant to scientists because the vast majority of human DNA, from one individual to the next, is the same at a given location. Therefore, it is these SNP’s, these places that vary by a single letter, which differentiate individuals and to a large extent, account for the unique characteristics of you. SNP’s amount to a single-letter change in the spelling of a “protein word” and as we noted earlier, sometimes a change alters the meaning of the word and sometimes it doesn’t but, in either case, SNP’s can tell us a small part of your genetic story.

What is Genomic Profiling Test?

Genomic profilng test is the concurrent detection of multiple gene variants that have been associated with predisposition to a particular disease. Virtually all-human diseases result from the interaction of genetic susceptibility and modifiable environmental factors, broadly defined to include infectious, chemical, physical, nutritional, and behavioral factors. Genetic variants, SNPs, are associated with almost all diseases, though they do not cause disease but influence a person's susceptibility to specific environmental factors that increase disease risk.

Health conditions are not caused by genes alone. Instead, they develop when many potentially harmful factors-both genetic and environmental-interact over a long period of time. Only by considering all of these factors together can a person accurately estimate his or her unique health risks and take the right steps to help prevent chronic disease from developing.

Importance of Genomic Profiling

The increasing understanding of genomic profiles has the potential to usher in a revolution of personalized healthcare and disease prevention. The assumption driving this increased intensity in genomics research is that individuals will be able to use their genomic profiles to reduce their risk of common conditions, such as heart disease, diabetes and obesity, or to improve overall health and well-being.

Advances in genetics and the sequencing of the human genome will ultimately result in a comprehensive understanding of the molecular underpinnings of human development, health and disease. Hundreds of reports of gene-disease associations have already been published, and knowledge about the interactions between genetic and environmental factors is increasing day by day.

Genomic profiles, one of the newest approaches to personalized medicine, consists of the concurrent detection of multiple gene variants that have been associated with greater risk or predisposition to a particular disease or condition. The profiles are proposed as a means to identify individual risk, for the purpose of tailoring specific risk-reducing actions, typically involving vitamins, environmental exposures, diet or other lifestyle changes that are expected to prevent disease.

How gene variation help to diagnose a disease?

Each person's genetic material contains a unique SNP pattern that is made up of many different genetic variations. Researchers have found that most SNPs are not responsible for a disease state. Instead, they serve as biological markers for pinpointing a disease on the human genome map, because they are usually located near a gene found to be associated with a certain disease. Occasionally, a SNP may actually cause a disease and, therefore, can be used to search for and isolate the disease-causing gene.

To create a genetic test that will screen for a disease in which the disease-causing gene has already been identified, scientists collect blood samples from a group of individuals affected by the disease and analyze their DNA for SNP patterns. Next, researchers compare these patterns to patterns obtained by analyzing the DNA from a group of individuals unaffected by the disease. This type of comparison, called an "association study", can detect differences between the SNP patterns of the two groups, thereby indicating which pattern is most likely associated with the disease-causing gene. Eventually, SNP profiles that are characteristic of a variety of diseases will be established. Then, it will only be a matter of time before physicians can screen individuals for susceptibility to a disease just by analyzing their DNA samples for specific SNP patterns.

How Genetic variation (SNPs) help in Drug Development?

As mentioned earlier, SNPs may also be associated with the absorbance and clearance of therapeutic agents. Currently, there is no simple way to determine how a patient will respond to a particular medication. A treatment proven effective in one patient may be ineffective in others. Worse yet, some patients may experience an adverse immunologic reaction to a particular drug. Today, pharmaceutical companies are limited to developing agents to which the "average" patient will respond. As a result, many drugs that might benefit a small number of patients never make it to market.

In the future, the most appropriate drug for an individual could be determined in advance of treatment by analyzing a patient's SNP profile. The ability to target a drug to those individuals most likely to benefit, referred to as "personalized medicine", would allow pharmaceutical companies to bring many more drugs to market and allow doctors to prescribe individualized therapies specific to a patient's needs.