Distribution of glucose-6-phosphate dehydrogenase phenotypes in five East Asian population groups.

1205 adult males comprising 287 Chinese from Singapore, 448 Thais, 123 Filipinos, 140 Koreans and 207 Taiwanese were investigated for the phenotypic distribution of red cell G6PD by starch-gel electrophoresis. The incidence of the deficient alleles (GdB- and Gd-) was found to be as follows: Chinese - 8%, Thais - 6.7%, Filipinos - 13%, Koreans - 3.5%, and Taiwanese - 11.6%. Low frequency of fast variant of Gd with normal activity was observed in Filipinos (0.8%), Koreans (2.1%) and Taiwanese (0.5%). Two slow variants of Gd alleles with normal activity were detected. The one with 95% mobility was present in Chinese (2.1%), Thais (1.6%), Filipinos (0.8%), Koreans (1.4%) and Taiwanese (1.0%), while the other slower variant was encountered only in Chinese (1.0%) and Thais (0.2%). One instance of Gd B with about 150% enzyme activity was detected in a Thai. Partially deficient fast variant of G6PD was observed in one Thai and one Filipino.