GSTM1 and cholelithiasis: Conflicting data have been reported in the literature regarding the role of alpha thalassemia in bilirubinemia and cholelithiasis in SCA.1,4,11,13 In our study, although the coexisting alpha thalassemia diminished the hemolysis in a gene dose-dependant manner (low LDH and reticulocyte numbers and higher Hb), it did not influence the rate of gall stone formation.