A North West MP has called for a public debate about the high numbers of birth defects among children from marriages between first cousins in Britain's Asian communities.
Phil Woolas said that while health workers were well aware of the heightened risk of genetic problems, cultural sensitivities made the issue difficult to raise.
The Government minister, who represents ethnically-diverse Oldham East and Saddleworth, said: "Part of the risk, I am told by the health service, is first-cousin marriages.
"If you are supportive of the Asian community then you have a duty to raise this issue."
His call was supported by fellow Labour MP Ann Cryer who first raised the issue more than two years ago after research showed British Pakistanis were 13 times more likely to have children with recessive disorders than the general population.
She blamed a "medieval culture" of keeping wealth in the family and said some couples ignored warnings not to have more children despite the risks.
The comments come at a sensitive time for community relations following the Archbishop of Canterbury's controversial comments about accommodating aspects of sharia law in Britain.
But Mr Woolas insisted that the marriages - which are perfectly legal in the UK - were a cultural, not religious, issue based in the traditions of rural parts of Pakistan.
"Awareness does need to be raised but we are very aware of the sensitivities," he added, pointing out that many of the people involved were the products of such marriages themselves.
Mrs Cryer, who represents Keighley in West Yorkshire, told The Sunday Times: "If you go into a paediatric ward in Bradford or Keighley you will find more than half of the kids there are from the Asian community.
"Since Asians only represent 20%-30% of the population, you can see that they are over-represented."
