- Participants with Gilbert's syndrome will be eligible for the study. A diagnosis of Gilbert's syndrome will be based on the exclusion of other diseases based on the following criteria: (i) unconjugated hyperbilirubinemia noted on several occasions; (ii) no evidence of hemolysis (normal hemoglobin, reticulocyte count, and Lactate dehydrogenase); (iii) normal liver function tests; (iv) absence of other diseases associated with unconjugated hyperbilirubinemia