Friendships are in the genes
A new genetic study shows that we share more DNA with our friends than with strangers.
Friends really are like family, a new genetic study has found. People who are friends are much more likely to share a number of closely related genes, researchers from the University of California-San Diego and Yale University revealed, after examining the DNA of thousands of pairs of biologically unrelated friends with pairs of unrelated strangers living in the same area.
"Looking across the whole genome we find that, on average, we are genetically similar to our friends. We have more DNA in common with the people we pick as friends than we do with strangers in the same population," said Professor James Fowler, co-author of the study.
In fact, the study shows that, on average, friends share about 1 per cent of their genes – about the same overlap as we can expect to find among fourth cousins. The authors explained that it makes sense that we have these shared genes among social networks, because it would have had evolutionary advantages. "The genes we share are the genes that evolved fastest. Human friendship has turbocharged evolution," Professor Fowler said.