UGT1A1

Gilbert’s syndrome is caused by decreased hepatic levels of the enzyme glucuronosyltransferase. As this enzyme is responsible for the glucuronidation (conjugation) of bilirubine in the liver, reduced activity of the glucuronosyltransferase leads to the accumulation of unconjugated bilirubin in the circulation.

It is not a rare disease: 3-10% of the population presents this condition.