Inbreeding resulting from first-cousin marriages in Islam has worked profound changes on their gene pool, affecting intelligence levels as well as measures of mental and physical health. According to the research of Sennels, almost half the world’s Muslim population are inbred. In Pakistan, inbreeding approaches 70%. Even in England, more than half of all Pakistani immigrants are married to first cousins, and in Denmark that figure is around 40%. The numbers are equally devastating in in other Muslim countries: 67% in Saudi Arabia; 64% in Jordan and Kuwait; 63% in Sudan; 60% in Iraq; and 54% in the United Arab Emirates and Qatar.
According to the BBC, inbreeding by Pakistani Muslims explains why British Pakistani families are 13 times more likely to bear children with recessive genetic disorders. And while Pakistani births are only 3% of all births in the UK, they account for 33% of all children with genetic birth defects. The risks are 18 times higher of bearing offspring with cystic fibrosis and spinal muscular atrophy, and the risks are 10 times greater for deaths due to malformations. Other adverse negative consequences of inbreeding include a 100% increase in the risk of stillbirths and a 50% increase in the possibility that a child will die during the birth process.
Reduced intelligence is another consequence of Muslim marriage patterns. According to his research, Sennels demonstrates that offspring from inbreeding have IQs 10 to 16 points lower than offspring of other marriages, and they develop much slower socially. The risk of having an IQ lower than 70–the official standard for “retarded”–increases by an astonishing 400% among children of first cousin marriages.