Abstract
DNA samples from 29 males with the G6PD A-phenotype and 14 males with a G6PD B phenotype were studied for the presence of each of four polymorphic restriction sites in the glucose-6-phosphate dehydrogenase locus. All G6PD A-subjects with the G6PD A-202A/376G genotype, regardless of population origin, shared identical haplotypes. In view of the fact that at least one of the restriction sites, the PvuII site in the intron between exon 5 and 6, has thus far been uncommon in the populations studied, it seems likely that the G6PD A-mutation at nucleotide 202 arose relatively recently and in a single individual.