Personalized Medicine - Translational Informatics: Realizing the Promise of Knowledge-Driven Healthcare - page 44

Fig. 3.6 Interface for a 23andMe health report (no longer offered to new customers). The odds
calculator shows the estimated incidence of a disease for a person sharing this individual's gender,
ethnicity, and genotype for the selected markers. Only markers that are included in 23andMe's
gene chip are included in the calculation, and the relative risk shown does not factor in environ-
ment or lifestyle, which are both known to play a role in one's risk for disease (©23andMe, Inc.
2013. All rights reserved; distributed pursuant to a limited license from ©23andMe)

ability to inform customers of their risk for specifi c diseases and conditions, and
stopped offering health-related reports for anyone who purchased a kit after the date
when the FDA issued its letter at the time of writing, (and take out the work “now”).
The company's website now indicates that they provide ancestry information and raw
genomic data, but that they have suspended health-related genetic reports [ 28 ].

3.4.3 Sequencing in Rare Diseases

Rare diseases are very diffi cult to detect using GWAS due to the “guilt by associa-
tion” approach that SNP chips necessitate. DNA sequencing to determine genomic
variation can have far greater resolution to pinpoint the actual functional variant.
Indeed, there have been some spectacular successes using this approach, some of
which have been picked up by the mainstream media. As one example, in 2007, a
2-year-old boy named Nicholas Volker had a mysterious and excruciating bowel
condition. Whole exome sequencing allowed researchers to compare his DNA with
the human reference genome in order to determine the likely culprit. Researchers
were able to identify 1,500 novel mutations in Nic's genome. A causal muta-
tion was identifi ed and, equally as important, a known treatment was available.