The NT 1311 polymorphism of G6PD: G6PD Mediterranean mutation may have originated independently in Europe and Asia.

A polymorphic site exists in exon 11 of G6PD: in the wild-type enzyme, nucleotide (NT) 1311 is a C, but is some individuals from diverse populations a T is present instead. Nine of 54 X chromosomes from Europeans of mixed origins, nine of 41 X chromosomes of Ashkenazi Jewish subjects, three of 18 X chromosomes of Sicilians, five of 20 African X chromosomes, and nine of 20 Asian Indian X chromosomes had the mutant genotype. In contrast, the mutation was found in only three of 59 Oriental X chromosomes and in three of 30 Central/South American X chromosomes. The mutation was absent from four samples of chimpanzee DNA. Twenty-one of 22 male subjects from Mediterranean countries who had the G6PD Mediterranean 563T genotype investigated in the present study or reported previously had a T at NT 1311. Only one had the normal C at NT 1311. In contrast, both G6PD Mediterranean563T males from the Indian subcontinent had the normal C at NT 1311. These findings suggest that the same mutation at nucleotide 563 giving rise to G6PD Mediterranean may have arisen independently in Europe and in Asia.