Can't Stay Faithful? Blame Your DNA

Have a tendency to cheat or sleep around? It may not be your fault. A new study shows that people with a particular version of the dopamine receptor gene DRD4 are more likely to be unfaithful or have one-night stands, LiveScience reports. The same gene has already been linked to other thrill-seeking activities including alcoholism, gambling addiction, and horror film fandom. It was also recently linked to a tendency toward political liberalism.

The new study, published in the online journal PloS One, analyzed the sexual history of 181 young adults and found that those with the thrill-seeking gene were about twice as likely to have had uncommitted sex. "The motivation seems to stem from a system of pleasure and reward, which is where the release of dopamine comes in," says a researcher. "In cases of uncommitted sex, the risks are high, the rewards substantial, and the motivation variable—all elements that ensure a dopamine 'rush.'"
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