Disorders caused by recessive mutations are normally rather rare. But not in Lahore; nor in Leeds. That's because of the Pakistani way of marriage. Most of us marry people quite distantly related to ourselves and, as we travel ever further, our mates become ever more genetically remote.I wonder what else about the region this explains...In Pakistan, however, some 60 per cent of marriages are between first cousins; the frequency in Bradford and Leeds is thought to be comparable. The result is that clinical genetics units serving the British Pakistani community see a range and frequency of genetic disorders unknown elsewhere in the country.
Cousins marry cousins for another reason: women are so badly treated that they need the protection of a close male relative to the groom. Mamoud maybe won't beat his uncle's daughter: Uncle might beat on him.