Molecular Aspects of α-Thalassemia in Myanmar
We studied an occurrence of α-thal genes in 191 cases (117 children, age ranged from nine months to 12 years; 69 adults, age ranged from 13 to 66 years; and five parents) from Myanmar. Different racial (Myanmar, Chinese, Indians, Muslims) and ethnic groups (Bamar, Kayin, Mon, Rakhine, Shan, Kachin, Chin) involved. Except the parents, they were diagnosed as thal major and under regular blood transfusion. Polymerase chain reaction (PCR) using primer sets specific for three common α-thal mutations (-α3.7, -α4.2, and -SEA genes) was applied to DNA samples collected from all of the cases. A total of 33 samples (17%) were found to have α-thal mutations and distributed as follows: (a) 16 were α-thal-2 having -a3.7/αα genotype, (b) 10 were α-thal-1 having -a3.7/-α37 genotype in two cases and --SEA/αα genotype in eight cases, and (c) seven cases were Hb H disease having -α3.7/-SEA genotype. The -α4.2 gene was not detected. Four of these α-thal patients were also Hb E carriers. The findings from this study demonstrated a high prevalence of α-thaｌ and Hb E in Myanmar and, then, increased frequency of Hb E-α-thal should be expected. This work could firstly describe a molecular situation of α-thal occurring in thal major patients of Myanmar.