Friend Study Finds That We Pick BFFs Who Are Genetically Similar

Friend study researchers have found a genetic link between you and your bestie.

According to the new study, published Monday in the scientific journal Proceedings of the National Academy of Sciences, people are likely to select friends who are genetically similar to themselves, to the extend that they tend to be as alike genetically as fourth cousins.

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The findings were based on an examination of about 1.5 million markers of genetic variations in a group of nearly 2,000 people who had taken part in a long-running health study based in Massachusetts. The researchers compared people identified as friends to those who were not.

The study showed people were most similar to their friends in olfactory genes, which involve the sense of smell, and were least similar in relation to immune system genes.

“Olfactory genes have a straightforward explanation: People who like the same smells tend to be drawn to similar environments, where they meet others with the same tendencies,” said researcher James Fowler, a professor of medical genetics and political science at the University of California, San Diego.

The friend study follows on the heels of research issued last May that found people tended to choose spouses with similar DNA.

Fowler indicated the new findings made it clear people have more DNA in common with chosen friends than with strangers of the same population. Fourth cousins, he notes, are people with great-great-great grandparents in common.

Because study participants were largely homogeneous — whites of European background — the results “are less likely to be driven by the simple explanation that people of similar ancestry befriend one another,” Fowler said.

Nicholas Christakis, a fellow researcher of Fowler’s from Yale University, said how people choose friends with similar genetics remains a mystery.

“It could involve the workings of a postulated ‘kin detection system’ in humans,” Christakis said. “Our fates depend not only on our own genes, but also on the genes of others around us, and in particular our friends.”

Christakis admits he’s interested in discovering why people have friends in the first place.

“The making of friends is exceedingly rare in the animal kingdom,” said Christakis. “Certain other primates, elephants and whales are the only other mammals who do this, and this alone aroused our curiosity.”

Are you surprised by the findings of this friend study?

Do you think that you and your best friend may be related?

Share your thoughts with us in the comments section below.

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