First cousins who marry run twice the risk of having a child with genetic abnormalities, according to the findings of a study based on the English city of Bradford.
The city, which has a high proportion of South Asian immigrants and their descendants among its population, served as a microcosm for examining the risk of blood relative couplings.
About 37 per cent of marriages among people of Pakistani origin in the study involved first cousins, compared with less than one per cent of
British unions, said the researchers.
University of Leeds investigator Eamonn Sheridan led a team that pored over data from the
Born in Bradford study, which tracks the health of 13,500 babies born at the city’s main hospital between 2007 and 2011.
Out of 11,396 babies for whom family details were known, 18 per cent were the offspring of first-cousin unions, mainly among people of Pakistani heritage.
A total of 386 babies — three per cent — were born with anomalies ranging from problems in the nervous, respiratory and digestive systems, to urinary and genital defects and cleft palates.
This Bradford rate was nearly twice the national average, said the study published in medical journal The Lancet — via redwolf.newsvine.com