Picture: Pixabay DNA might be to blame for OCD

It has long been thought to be a purely psychological condition. But obsessive compulsive disorder (OCD), which David Beckham famously suffers from, could be written in our genes.

Scientists identified four genes which are linked to the disorder and suggest that a brain misfire could make people obsess over repetitive behaviours.

Similar genes have been found in mice and dogs, which can obsessively chase their tail or lick themselves.

Writing in the journal Nature Communications, researchers led by the Broad Institute in Massachusetts state: ‘Isolating and characterising such genes are important for understanding the biology and developing treatments for this devastating disease.’

Former football star Beckham, 42, has spoken of a compulsion to count clothes and put magazines in straight lines. Previous studies suggested genes might be involved, but it had not been confirmed.

Lead author Dr Hyun Ji Noh said: ‘Each additional species that we looked at gave us more information about possible factors in the brain that contribute to OCD.’ The genes were compared against two previous genetic studies in people, including more than 1,300 with OCD and 1,600 who did not have it.

The findings could lead to new OCD treatments as current drugs, which target serotonin-signalling in the brain, only work for a small group of people.