However, they have reported the presence of another atypical haplotype that could be considered as specific to Tunisian chromosome βS. In a previous study we have been interested in the implication of the polymorphism A(TA)nTAA of UGT1A1 in occurrence of cholelithiasis among Tunisian patients with normal hemoglobin status. This evidence concerns the gene UGT1A1 and cholelithiasis.