High incidence of 3-thalassemia, hemoglobin E, and glucose-6-phosphate dehydrogenase deficiency in populations of malaria-endemic southern Shan State, Myanmar.

Samples from 916 members of various ethnic groups from malaria-endemic southern Shan State, Myanmar, were analyzed for 3-thalassemia (3-thal), 3-thalassemia (3-thal), abnormal hemoglobin variants, and glucose-6-phosphate dehydrogenase (G6PD) deficiency. Of these subjects, 530 (57.9%) were found to have at least one of these red cell genetic disorders. The overall frequencies for the various red cell genetic disorders were as follows: 3-thal, 37.5% (343/916); hemoglobin E (Hb-E), 20.3% (186/916); G6PD-Mahidol, 17.5% (160/916); and 3-thal, 0.3% (3/916). The frequencies of combined disorders were 6.9% (63/ 916) for 3-thal/Hb-E, 5.7% (52/916) for 3-thal/G6PD-Mahidol, 2.8% (26/916) for Hb-E/G6PD-Mahidol, 1.1% (10/916) for 3-thal/Hb-E/G6PD-Mahidol, and 0.1% (1/916) for 3-thal/3-thal/G6PD-Mahidol. Of the various ethnic and non-ethnic groups, the Bamar population showed the highest frequencies of 3-thal (56.9%, 177/311), Hb-E (28.3%, 88/311), and G6PD-Mahidol (21.2%, 66/311) (all duplicated and triplicated cases were included). In addition, 2 new mutations, an 3 gene triplication (/333(anti3.7); 0.2%, 2/916) and Hb-Neapolis (0.1%, 1/916), were detected. Our results showed that race was the dominant factor affecting the frequencies of red cell genetic disorders in malaria-endemic areas of Myanmar.