A trio of researchers at Peking University says it has uncovered a gene variant that increases the likelihood that a young adult is in a romantic relationship.
Peking's Xiaolin Zhou and colleagues note, psychological and sociological studies have found that socioeconomic status, looks, and personality all influence romantic relationship formation, but they add that genetic variants are also part of the equation.
As they write in Scientific Reports, they examined the 5-HT1A genotype of 579 Chinese undergraduate students and their relationship status. The 5-HT1A gene influences serotonin levels, and the G allele of the C-1019G (rs6295) polymorphism is associated with lower levels of serotonin than the C allele is.
The found that about half of the students with a CC genotype and nearly 40 percent with CG/GG genotypes were in a relationship. That is, students with CG/GG genotypes were more likely than those with the CC genotype to be single. This effect, the researchers report, holds even after controlling for appearance, parental income, and other socioeconomic factors.
"These findings provide, for the first time, direct evidence for the genetic contribution to romantic relationship formation," Zhou and colleagues say.
Still, the Guardian notes that the gene explains only a small fraction — 1.4 percent — of the difference in likelihood of being single or in a relationship. "Whilst genetic factors will inevitably influence relationship status, this specific marker accounts for only a very small part of that, and on its own has little bearing on whether an individual is in a relationship or not," Kings College London's Thalia Eley tells the Guardian.