G6PD UBE, A GLUCOSE-6-PHOSPHATE-DEHYDROGENASE VARIANT FOUND IN 4 UNRELATED JAPANESE FAMILIES

Abstract

A total of 6120 Japanese males were screened for glucose-6-phosphate dehydrogenase deficiency (G-6-P D). Five cases with the deficiency were discovered. Two of them and an additional 2 cases have the same variant, G-6-P D Ube, characterized by moderate enzyme deficiency, fast moving enzyme activity on electrophoresis, high Ki [inhibition constant] NADPH, utilization of substrate analogues, kinetics, pH optima and stability. This variant was distinguished for G-6-P D A- and from other Oriental variants by biochemical parameters. Differences in the frequency and type of the variants between southern Asia and Japan suggest that the Japanese who were isolated on islands where malaria is not endemic may have developed their own variant traits.