You and your friends are genetically similar, why?

There are friends who can not care about anyone, but the opportunities to become friends are various. However, human beings unconsciously point out the possibility that they survived by choosing "a person genetically similar to theirs" as a friend.

[1308.5257] Friendship and Natural Selection
https://arxiv.org/abs/1308.5257

Friends Are Genetically Similar | Accumulating Glitches | Learn Science at Scitable
https://www.nature.com/scitable/blog/accumulating-glitches/friends_are_genetically_similar

The research team of Dr. James Fowler of the University of California and Dr. Nicholas · Cristaquis of Yale University reported that long-term cardiovascular disease research data "has a genetic similarity between a person and her friend" I discovered the fact that. The degree of similarity is only 1%, but this is unconscious out of friends who have genetic similarity from other people with similarity as relatives with the same high-grandfather (grandfather's grandfather) I know that you have selected it.

Dr. Fowler used what "Framingham Heart Study(Framingham heart study) "Research data called. The Framingham Heart Study is a large-scale survey of residents of a small town called Framingham in a long-term survey conducted by the Framingham Institute since 1948 to ascertain the risk factors for heart disease. Framingham was chosen because there are few people coming and going because it is suitable for finding risk factors. Since the Framingham heart research, which is a large-scale study, combines social relationships with genetic data, it is the only research in the world as a meaningful scale, so the research team is going to investigate the relationship between genes and friends It seems there was.


After knowing the tendency to "have a common genome with friends", researchers next examined the genotypes of what kind of genes are common. Very interestingly, it seems that commonality was seen in genes related to olfaction.

Other studies have also pointed out that odors are used to evaluate potential fellows' immune responses, but the findings from the Framingham heart study "the commonality of genetic information on olfaction with friends" It is possible that humans are using the smell to distinguish potential fellows.


Background to the evolution of humans is not only physical and ecological factors but also the social environment as a major factor. The ability to cooperate not only with relatives but also genetically close others seems likely to have benefited human beings that are social animals. Dr. Cristaquis said, "Our adaptability seems to depend not only on our own genetic make-up but also on the genetic makeup of our friends," said the human beings genetically similar I point out the possibility that it has evolved in the direction of searching for "friends".