Genetic Testing Kits Are Coming to Walgreens

Walgreens stores across the United States will soon begin selling several different genetic testing kits, including those for genetic diseases, and drug sensitivity (1). The kits are manufactured by Pathway Genomics, a company that is based in San Diego.

Pathway Genomics' genetic testing kit, which will cost between $20-$30, includes a saliva collection kit, instructions, and a postage-paid envelope for returning the saliva sample to the company's lab. The person who submits the saliva sample can then log into the company's web site and order specific Genetic Insight tests, such as the Drug Response, Pre-Pregnancy Planning, and Health Conditions Insight tests. So far, the Pathway Genomics kits will not be made available through Walgreens stores in New York due to stricter genetic testing state laws.

Pathway Genomics already offers several different genetic testing kits through its web site, including a kit that determines ancestry (2). The Pathway kits operate by testing the amount of single nucleotide polymorphism (or SNP, pronounced "snip") within discrete areas of a person's genome. A SNP occurs when a single nucleotide - either an A, C, G, or T- is different in one person's versus another person's DNA. SNPs can occur in coding regions of DNA as well as non-coding regions. A coding region of DNA is defined as a strand of nucleotides- for example ATGGTGAATTAG- that is recognized and expressed as a product (e.g., protein). Alternately, a non-coding region of DNA is a strand of nucleotides that might still serve a function within the genetic code of the person, but which is probably not expressed as a product.

When SNPs occur in the coding regions of DNA, they can lead to an increased likelihood of carrying or developing a genetic disease like Tay-Sachs or Alzheimer's. This happens because a change in a single nucleotide can alter the final product of the respective gene. For example, a protein that is encoded by a string of nucleotides such as ATGGTGAATTAG (methionine-valine-asparagine) will be expressed as a set of different amino acids compared with a protein encoded by a string of nucleotides such as ATGGTGAAATAG (methionine-valine-lysine). These two strings of nucleotides differ by only one single nucleotide. However, as a result of that difference, some of the final amino acids that are expressed are different. A difference of only one amino acid can lead to a protein becoming mis-folded, degraded, or non-functional.

Other SNPs can be quite specific to a given population, allowing researchers to determine the origins and world travels of this population throughout history. The frequency of such SNPs (especially if they are not detrimental to the health or reproductive success of the population) can even become characteristic of a given race, tribe, or group of people.

Given the fact that SNPs can indicate a propensity for certain diseases, Pathway Genomics now intends to capitalize on its Insight kits by selling them commercially. However, some experts at the U.S. Food and Drug Administration (FDA) disagree with this maneuver, citing that there is not enough information on whether the kits will work as claimed (3). There is also concern that consumers will take drastic actions based on the results of these tests which, even if they do work, do not guarantee that one will develop or have a child with a given disease. To this end, Pathway Genomics had previously stated that genetic counseling is a must when trying to determine the certainty that one will develop a disease or give birth to a diseased offspring (4). In other words, the company's Insight kits are merely the first step towards learning about one's genetics.

More recently, the FDA has notified Pathway Genomics that the company is required to provide proof of FDA clearance or an approval number for the genetic test kit (5). The FDA has given the company 15 days by which to comply with this request. in the interim, Walgreens has decided to place the stocking of the genetic kit on hold until this request from the FDA is addressed.

References:

1. Walgreens to Sell Pathway Genomics' Sample Collection Kit http://www.genomeweb.com/dxpgx/walgreens-sell-pathway-genomics-sample-collection-kit

2. Pathway Genomics http://www.pathway.com/how_it_works

3. Genetic Tests, Right Next to the Exlax http://www.genomeweb.com/blog/genetic-tests-right-next-exlax

4. Pathway Genomics Licenses Access to Harvard Health Information http://www.genomeweb.com/dxpgx/pathway-genomics-licenses-access-harvard-health-information

5. FDA Seeks Information from Pathway Genomics on Genetic Test Product http://www.genomeweb.com//node/940604?hq_e=el&hq_m=715269&hq_l=2&hq_v=b8c79cd5ef