You may have as much in common genetically with your friends as with your fourth cousins! Shutterstock
A new study, which the researchers themselves are calling “unusual,” posits that friends share more genetic markers than do strangers. Although the findings are intriguing, several scientists have voiced their concerns about professors James Fowler and Nicholas Christakis’ “kinship coefficient.”
Looking at differences between nearly 2,000 people, recruited as part of a heart study in a small US town, they found that friends shared about 0.1% more DNA, on average, than strangers…Other researchers have expressed concern about different factors that could affect the results - such as ethnicity or other types of “population stratification” - which could make people both genetically similar and more likely to be friends.
Dr Rory Bowden, a statistician and lecturer at the Wellcome Trust Centre for Human Genetics in Oxford, also expressed reservations about whether the study could be confounded by “very subtle genetic population structure”.
“I wonder whether [these methods can fully account for] factors known to drive friendships, like church membership, sports or other cultural affinities, that would also lead to a correlation with genotype,” he said, “because they reflect differences in places of origin within Europe of the Framingham participants.”