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A BBC report^[2] found that Pakistanis in Britain, 55% of whom marry a first cousin, are 13 times more likely than the general population to produce children with genetic disorders, and that one in ten children of cousin marriages either die in infancy or develop a serious disability. Thus Pakistani-Britons, who account for some 3% of all births in the UK, produce "just under a third" of all British children with genetic illnesses.

A second-cousin mating entails an additional risk of birth defects that many authorities assess at about 1 in 100 — the same risk as that of a woman producing offspring at age 35 or, again, that of an even younger man.

^{Source: http://en.wikipedia.org/wiki/Cousin_couple}

^Nepali