Among subjects carrying a non-α0-thalassemia gene (including α+-thalassemia, β-thalassemia and Hb E) and a normal hemoglobin type, the IC ζ and i+LAB α THAL IC strip tests showed irregular patterns that were independent to their α- or β-globin gene abnormalities. The gene discussed is GSTM1; the disease is thalassemia.