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Friendship Genetics

July 21, 2014

Your friends may be as closely related to you as a fourth cousin.



Phillippe Put Flickr 7223675784_4a08b12708_o

(Phillippe Put/Flickr)

Where friends and family meet. I’m Bob Hirshon and this is Science Update.

Your friends may be more closely related to you than to strangers, according to a new study. Nicholas Christakis of Yale University and James Fowler of UC San Diego analyzed the social networks and genetic relationships of over 2000 people. Fowler says on average, friends were as closely related as fourth cousins.

JAMES FOWLER (University of California, San Diego):

It’s like they share a great-great-great-grandparent in common.


The researchers found that a similar sense of smell may be one of the genetically influenced mechanisms that brings friends together in the first place. But their shared genes could also give friends a survival advantage.


We’ve found that the genes that tend to be similar between friends are those that are evolving the fastest. In other words, it’s some tentative evidence that our social networks may be turbo-charging evolution.


The researchers hope to look at shared genes within much larger social networks in the future. I’m Bob Hirshon, for AAAS, the science society.