Gilbert's syndrome

Gilbert syndrome is a benign cause of mild unconjugated hyperbilirubinemia. The prevalence is 12% in caucasian males and 5% in caucasion females. The syndrome is caused by impaired hepatic glucuronidation of bilirubin by UDP-glucuronosyltransferase (UDPGT). Most cases are due to an extra TA dinucleotide in the TA repeat sequence in the promoter for this enzyme.

Indication For Testing

Patient’s with isolated unconjugated hyperbilirubinemia where a more definitive diagnosis of Gilberts syndrome is required.

Interpretation

• Normal:

TA6 repeats were detected in the promoter region of the UDPGT gene . This excludes the common cause of Gilberts syndrome.

• Abnormal:

Homozygous TA7 repeats were detected. This finding is associated with Gilberts syndrome.

 

Other rare mutations in the UDPGT gene also exist and may influence bilirubin metabolism.