Cheating not our fault, scientists say

Love rats like Tiger Woods have a new defence - it's not their fault, it's the fault of their genes.

Scientists at the State University of New York claim that up to one in four people are genetically predisposed to being unfaithful.

Research carried out at the university found that people with a particular gene variant were twice as likely to play away from home. Almost 200 people were surveyed.

"What we found was that individuals with a certain variant of the DRD4 gene were more likely to have a history of one-night stands and infidelity," said researcher Justin Garcia.

"The motivation seems to stem from a system of of pleasure and reward.

"In case of uncommited sex, the risks are high, the rewards substantial and the motivation variable;  all elements that ensure a rush.

The one in four with the desire to cheat will not necessarily go through with the dirty deed, Garcia explained.