The alleles differ in the number of repeats from 5 to 8 with (TA)6 allele being the common allele in Caucasians.7 There is an inverse correlation between the number of repeats and hepatic expression level of the UGT1A1gene on the one hand, and on the other, a direct correlation between the number of repeats and bilirubinemia.9,10 However, the relationship of UGT1A1 polymorphism, both with hyperbilirubinemia and with the incidence of cholelithiasis is not that straightforward. The gene discussed is UGT1A1; the disease is cholelithiasis.