UGT1A1 and autosomal dominant cerebellar ataxia: In the current study we tested 102 SCA Tunisian children patients among whom 52 have cholelithiasis and 76 subjects were chosen as control group characterized with normal hemoglobin status and presence of cholelithiasis and analyzed the polymorphism at the promoter and the relationships between the various UGT1A1 promoter genotypes and alleles and bilirubin levels.