We have performed molecular analyses of G6PD deficiency cases found in Laos, Myanmar, Thailand, Indonesia and Japan.
1. All of 8 Laotian cases proved to have G6PD Viangchan.
2. In Myanmar and Thailand, 15 cases (11 Burmese, 3 Mon and 1 Shan) were found to have G6PD Mahidol, and one Burmese proved to have G6PD Union.
3. Of 6 G6PD-deficient subjects of Thai origin, 3 were associated with G6PD Viangchan, one with G6PD Mahidol and one with G6PD Vanua Lava. The other subject was a compound heterozygote for G6PD Union and G6PD Canton.
4. Of 6 subjects of Filipino origin, 5 had G6PD Viangchan, and the other two had G6PD Coimbra and G6PD Chatham, respectively.
5. In Halmahera island and Bulu island in Indonesia, we found 8 G6PD Vanua Lava cases and one G6PD Coimbra case. Two other Indonesian cases from Jawa island proved to have G6PD Chatham.
6. Of 11 subjects of Chinese origin, we identified G6PD Kaiping in 5 cases, G6PD Canton in 3 cases, G6PD Gaohe in one case and G6PD Mahidol-like in another case. The 11th subject was found to have a novel mutation 1291 G→A causing a unique class-2 variant G6PD Surabaya.
In summary, the southern Mongoloids may be classified into three groups in terms of G6PD mutations : Asian continent group (Chinese, Laotians, Thais and Burmese), Asian island group (Filipinos and some Indonesians), and Melanesian group (Melanesians and some Indonesians). Each group may be characterized by the typical G6PD mutations : G6PDs Canton, Kaiping and Mahidol ; G6PD Viangchan ; and G6PDs Union and Vanua Lava ; respectively.