GSTM1 and thalassemia: Hb A was properly identified in 138 samples belonging to the following categories: 41 samples with no hemoglobin disorders, 32 samples with thalassemia, 1 sample with Hb Constant Spring (CS), 2 samples with Hb Lepore Boston Washington (BW), 16 samples with heterozygote Hb S, 31 Hb S homozygote transfused, 1 Hb A/C, 10 Hb S/C with transfusion, and 4 Hb E heterozygote.