Genes may help explain why different people lose their virginity at different ages, according to a new study out of the University of Cambridge published in Nature Genetics.
Along with religious beliefs, family background, and peer pressure, genetic differences can account for a quarter of the variation in the age at which an individual first has sex. One of the genes linked to an earlier start to one's sexual odyssey, CADM2, is also correlated with risk-taking behavior and having a large number of children.
"There is a heritable component to age at first sex, and the heritability is about 25 percent, so one quarter nature, three quarters nurture," senior author John Perry told The Guardian.
The scientists found 38 gene regions that were associated with a higher or lower "age at first sexual intercourse," which apparently is a commonly recorded (and self-reported) data point in biobanking projects such as the UK BioBank. They then verified their results with data sets from Iceland and the US.
Having sex at a younger age is also associated with early puberty, the researchers said.
Ewan Birney, a bioinformatician at the European Bioinformatics Institute, who was not a co-author of the study, said it highlighted the value of large biobanking projects. "We can expect many more results with a similar approach in the future as researchers mine this resource," he said.