Thalassemia carriers have characteristic hematological parameters with mild anemia with microcytic hypochromic RBCs, increased red cell counts and normal RDW that could help screening and together with HbA2 quantification by Hb electrophoresis or HPLC, βTT can be easily diagnosed and screened for in high-risk groups like family members and relatives of thalassemia patients. The gene discussed is GSTM1; the disease is thalassemia.