Of course we know that all human beings are related, but sometimes genetic analysis drives this point home even more strongly. If you carry a rare variant in the Factor V Leiden gene – which has just been added to the Navigenics genetic testing service – you share a common ancestor with every single person who carries that variant.
Factor V (pronounced “factor five”) is a “founder mutation,” a genetic change that originated in one individual long ago and can now be found in that person’s descendants around the world. This mutation is present in two to 15 percent of Caucasians, but is rare in genetically distinct non-Caucasian populations.