We are at the start of the age of genomic medicine, and one of the possible concerns about genomic testing is that it can be used as a high fidelity form of paternity testing. Although instances of non-paternity may be quite high in certain groups, there hasn’t been a lot of discussion of actual cases where large-scale genomic profiling has caused problems because of discoveries of non-paternity.
However, an anonymous writer (naming himself George Doe) for Vox has written a short article on his experience purchasing direct to consumer genomic testing for himself and his parents: http://www.vox.com/2014/9/9/5975653/with-genetic-testing-i-gave-my-parents-the-gift-of-divorce-23andme
To summarize, he ordered the testing for himself and his parents, and using the capability designed to find biological relatives in a large database of genomes, found that his father has produced a son,”Thomas”, with another woman. Thomas had been put up for adoption and didn’t know anything about his biological parents or other relatives.
Often concerns about the paternity testing capability of these genomic tests are focussed on individuals finding out that their current father is not their biological father. This is an interesting instance of finding out that a previously totally unknown individual is a half-brother and the product of an adulterous union. In the effort to find previously unknown distant relations, a relation the family might not wanted to know about was uncovered and has led to considerable strife in the family, including the divorce of the parents.
I think it is important also to mention that we don’t know the longer term outcome for this family, including Thomas, and what the future will hold for them with this information.
As we go forward with the use of genomics in healthcare, cases like this one will be important to inform how this technology is to be used. When analyzing a genome, particularly for healthcare purposes, it is often very helpful to have genomic information from parents and siblings. This helps us to compare differences and look for genetic features which help our interpretation. However, we certainly need to be aware of potential pitfalls.