Infidelity could be the result of genetics, new research suggests.
Scientists from the University of Queensland in Australia claim to have found a specific gene which makes women more liable to stray while in a relationship.
They analysed data from 7,300 twins between 18 and 49 years old who were all in long-term relationships. Despite being in relationships, 9.8 per cent of the men from the study and 6.4 per cent of the women admitted to having two or more sexual partners over the course of the last year.
Identical twins share all of their genes whereas non-identical twins do not. This meant that genes could be identified which are present in those who have been unfaithful.
A comparison revealed that 63 per cent of the infidelity by men could be linked to a genetic marker. In women it was 40 per cent. Additionally, they found that infidelity among women could be connected to a specific variation in one particular gene: called AVPRIA.
Dr Brendan Zietsch is a research fellow at the University of Queensland and led the study. He said that the research indicates that “people’s genetic make-up influences how likely they are to have sex with someone outside their main partnership”.
He added that isolating specific genes to test for the likelihood of infidelity is very difficult because the “effect of any individual gene is tiny” and that thousands of genes can influence behaviour. For that reason he said that more research would be needed to confirm their finding about AVPRIA.
These results seem to back up earlier studies which found that people who are unfaithful in one relationship are likely to be unfaithful in the next.