Direct-to-consumer DNA testing is relatively new, thus it is unclear at this time what some of the consequences may be in the future. Consider this, you may discover a 1st cousin that is a child of an aunt/uncle that was placed for adoption as a child 40 years ago. This child would have been born in 1975, the year Fred Sanger published an article describing a technique for sequencing DNA. The Sanger sequencing method, and its modifications, fueled the genome era. Nobody - not even Fred Sanger - could have envisioned in 1975 how easy it is today to discover genetic relationships through broadly commercialized genetic testing. I expect there are things that will be discovered in the future due to the availability of genetic testing, but these future discoveries are not currently obvious. Recognize, however, that you control your test results. They can be deleted by you at any time.
Areas of Potential Concern in the Future
- Maternity and Paternity - as more people are tested, it will become increasingly easy to reveal personal identity through genetic relationships
- Forensics - DNA forensics currently uses a different set of genetic markers than what is used by 23andMe and similar companies; however, the availability of large databases of genetically characterized individuals is apparently attracting the attention of law enforcement
- Discrimination - genetic data related to health information could be used by employers or health insurance companies; however, laws exist that forbid these practices (e.g., Genetic Information Nondiscrimination Act)