What Information Can Exome Sequencing Provide?
Whether you’re trying to learn more about your ancestry or get to the bottom of a mysterious medical condition that’s impacted your quality of life, genetic testing is likely an avenue you’ll explore. Of course, genomics isn’t a one-test-fits-all world, which can leave you wondering if genotyping, whole genome sequencing or exome sequencing is the answer. In a surprising number of situations, exome sequencing could give you the information you need.
How It Works
In the world of genomics, genotyping and whole genome sequencing represent the two ends of the spectrum, with genotyping looking for very specific things, while whole genome sequencing maps out 3.2 billion base DNA pairs. While not a perfect compromise, exome sequencing can provide you with more detailed information than genotyping without the time and expense of mapping your entire genome.
Basically, exome sequencing looks at roughly one percent of your genome, focusing primarily on the 180,000 exons (aka protein-coding genes). Although this still leaves scientists with roughly 30 million base DNA pairs to sequence, the information found on these DNA pairs can help them find the mutations that cause many common and devastating diseases.
Unfortunately, a relatively small variance in your genetic code could make a major difference in your longevity, health and wellness. Once a genetic mutation is discovered on any of these 30 million base pairs, scientists can determine whether an individual has a higher likelihood of developing a particular medical condition. When discussing any sort of gene sequencing, it’s critical to make the distinction that a mutation creates an increased likelihood of developing a condition, not a medical certainty that the condition will occur.
The genetic mutations found during exome sequencing can uncover the likelihood of developing conditions such as:
- Alzheimer’s disease
- Miller syndrome
- Rare neurological disorders found in pediatric patients.
In addition, exome research has helped scientists discover a gene mutation that lowers blood lipid levels. With this information, exome sequencing may have made it possible for researchers to one day create more effective ways to lower blood cholesterol levels.
Although the cost of whole genome sequencing has remarkably declined in the last decade, it still hasn’t reached the level of affordability that would make it feasible for the average family to order for everyone in the household. Exome sequencing, on the other hand, is available for less than $1,000, depending on which lab service you use. While this may still be a little pricey for widescale use on the consumer level, it is becoming an increasingly cost-effective option for doctors and researchers hoping to gain a better understanding of how to treat certain conditions.
For families with a strong history of medical conditions linked to genetic mutations, spending the money for exome sequencing could assist in making the lifestyle choices necessary to minimize the risk of developing a particular condition. Learning that you don’t have the gene mutation linked to a disease could also provide a level of peace of mind that no amount of money could previously buy.