Couples expecting their first child should reconsider owning a cat if they have a family history of eczema, a new study suggests.

Researchers have discoverered a link between the disease and a specific inherited gene which normally works by producing a protein which protects the skin.

However, in around one in ten children the gene does not work properly, leaving them more open to allergies.

Researchers compared a high-risk group of 379 Danish infants who had the defective gene with a group of 593 babies from the general population in Manchester.

In both groups, they found that children with the defective gene were twice as likely to develop eczema in the first twelve months of life as those without the genetic anomalies.

However, the study suggested that having a cat further increased the risk of developing the disease.

Exposure to dogs, however, did not make any difference to the risk, according to the findings, published in the journal PLOS Medicine today.

The scientists said that more research on the link was required as the number of children who carried the defective gene and whose family owned a cat in the study was small.

Dr Hans Bisgaard, who led the research said: 'The message isn't to kill the cat.

'If you haven't got the mutation it doesn't matter if you have a cat. But if you have the mutation, a cat has an effect.'

He said parents could one day test children to see if cats put them at a greater risk of eczema, but said more research is needed into the link.