Further DNA analysis of the α- and β-globin genes revealed 3.7 kb deletional α+-thalassemia and also β26G > A mutation, corresponding to Hb E; therefore, this subject was a triple heterozygote for Hb A2-Mae Phrik, Hb E, and deletional α+-thalassemia. This evidence concerns the gene GSTM1 and thalassemia.