The Thai variant and the distribution of alleles of 6-phosphogluconate dehydrogenase and the distribution of glucose 6-phosphate dehydrogenase deficiency in Thailand

Abstract

The samples were taken from 3185 subjects from ten provinces throughout Thailand. In 1577 males the frequency of glucose 6-phosphate dehydrogenase deficiency was 11.98%. In the far south the gene frequency was 2.83%; in the remainder of the country the frequency did not vary significantly about a mean of 13.76%. The deficiency is of a severe type. The G6PD of all of the nondeficient individuals had the electrophoretic mobility of type B. The mean frequency of the A/B electrophoretic phenotype of 6-phosphogluconate dehydrogenase is 8.47%. The maximum frequency was in central and southern Thailand with a decline to the north and northeast. A variant form of 6-PGD, referred to as the Thai variant, has been found in which two additional electrophoretic components migrate anodally to the normal A band, confirming that the molecule is at least a dimer. The hypothesis is advanced that erythrocyte 6-PGD is determined by two genetic loci, only one of which is translated in leukocytes.