Variants of combinations of the AVPR1A gene have been found to be associated with promiscuity and ruthlessness in animals, the Sunday Times reported.

Each person carries two AVPR1A genes – one inherited from each parent – so there are a number of potential combinations.  

But these variations only appear to affect females rather than males.

Dr Brendan Zietsch, a professor of psychology at the university, worked with a team of geneticists and neuroscientists to examine the DNA and lifestyles of more than 7,000 people. 

They found that of the 6.4 per cent of women who had been unfaithful, a large amount of them had a specific variant of the ‘infidelity gene.’