What brings two people together, anyway? While psychologists engage in the similar-personalities vs. opposites-attract debate, a different group of researchers has found at least part of the answer may be even more basic.
Perhaps your DNA simply recognized a kindred spirit when it met one.
“We find that spouses are more genetically similar than two individuals chosen at random,” reports a research team led by University of Colorado sociologist Benjamin Domingue.
"Our results indicate that social institutions may segregate people on genotype (presumably unwittingly), which could be behind some of the (data) we observe."
Granted, the researchers write in the Proceedings of the National Academy of Sciences, the genetic match they found between husbands and wives (no gay couples were included in the study) isn’t as big as that for education levels. One of our strongest tendencies in the coupling realm is to marry people with roughly the same level of schooling as we have.
Nevertheless, the genetic similarity findings are interesting—especially since they were discovered in one large-scale survey (the University of Michigan Health and Retirement Study), and confirmed in another (the second generation of the Framingham Heart Study).
Analysis of “opposite-sex non-Hispanic white pairs within the U.S.” revealed that an increase in genetic similarity of one standard deviation “increases the probability of marriage by roughly 15 percent.”
The researchers note that it’s possible their findings reflect a wider social phenomenon.
“Previous research suggests that genetic similarity among friends is higher in schools with higher levels of economic inequality,” they write, adding that this may result in “genetic selection into friendships,” and, ultimately, romantic relationships.
“Our results indicate that social institutions may segregate people on genotype (presumably unwittingly), which could be behind some of the (data) we observe,” the researchers write.
It’s all great fodder for the next big self-help relationship guide: You’re Just Not My Genotype.