A new study reports that people born with a special variation of the DRD4 gene are more than twice as likely to cheat on their partners than those without: Researchers at the State University of New York in Binghamton interviewed 181 young adults about their sex lives, and half of those with a genetic variation called 7R+ reported engaging in one-night stands and being unfaithful, compared with only 22 percent of people without 7R+.
That variation is linked with high-risk, high-reward behaviors such as drinking and gambling — activities that provide a rush of dopamine. In other words, although cheating is socially ill-advised, it provides one hell of a high, much like having four too many vodka tonics. Those with 7R+ like that sensation more than others.
Researchers say not everyone with the gene will cheat, of course, and people without the gene could cheat too. But it couldn’t hurt to be wary of the dude who’s always at either the bar or the track.