The sickle genotype distribution of these 1144 patients was: 903 (78.9%) HbSS or HbSβ0-Thalassemia; 174 (15.2%) Hb SC; 48 (4.2%) with HbSβ+-Thalassemia; and 19 (1.7%) with HbSD. The gene discussed is GSTM1; the disease is thalassemia.