Chapter 22, Problem 30P

In 2008, Time magazine named as its invention of the year the development of personal genomics services by a company named 23andMe. Customers sent saliva samples to the company, which then genotyped approximately one million SNPs located across the genome, and communicated the data online to the customer along with what was claimed to be a “for education use only” assessment of potential risk for a variety of traits.

However, on November 22, 2013, the United States Food and Drug Administration (FDA) ordered 23andMe to stop marketing its personal genomics services because the accuracy of its SNP genotyping and risk predictions had not been validated as sufficiently accurate for medical use. The FDA was concerned that people might make serious medical decisions based on information from a test that was not clinically approved. Some elements of this ban were relieved in 2015 and 2017, but DNA testing services are still restrained from offering their customers all the pre-ban predictions. Defining these limits remains a contentious and unresolved issue.

a.	Can the information you would obtain from this personal genomics service tell you whether or not you have a Mendelian genetic disease? Explain.
b.	Can the information you would obtain from this personal genomics service inform you about your likelihood of having a disease that is a complex trait? Explain.
c.	In December 2013, a reporter for The New York Times reported that she sent samples of her own DNA to three different companies (one of which was 23andMe), but the three companies provided very different estimates of her risk for a variety of complex traits. What were the likely causes of the differences in these estimates?
d.	Do you think new scientific developments will help resolve these issues in the near future?