Friends are great. You share so much with them: interests, likes, perhaps even your latest crush! But now scientists are finding that best friends share much more than social and psychological traits – they even share genes!
Scientists at Yale and University of California, San Diego have found that we share a considerable amount of genetic material with our friends – close to 1% of the assembled DNA. It may seem small to many but in genetics, this value is practically off the charts! For some perspective, you also share 1% of your genetic code with your fourth cousins. This is when you share a great-great-great-grandparent. So, it looks like we seek out close friends who resemble our family.
To figure this crazy factoid out, scientists examined around 2,000 people in a racially and ethnically homogenous area. Usually, this is not the greatest way to conduct scientific studies, but in this case it is good because it rules out a tendency to befriend people who share our race. Continuing with the control group, they looked at around 1,300 pairs of friends and examined 1.5 million markers of gene variation within them.