GSTM1 and alpha thalassemia spectrum: The results confirmed 5 cases with heterozygous alpha-thalassemia-1 (–SEA/αα), one case with heterozygous alpha-thalassemia-2 (-α3.7/αα), one case with homozygous alpha-thalassemia-2 (-α3.7/-α3.7) and the other case with compound heterozygous alpha-thalassemia-1 and alpha-thalassemia-2 (-SEA /- α4.2), also known as Hb H disease (Supplementary Table S2).