Relation Between the Uridine Diphosphate Glucuronosyltransferase 1A1 Polymorphism and the Bilirubin Levels in Sickle Cell Disease

Abstract

Genetic variations in the promoter of uridine diphosphate (UDP)–glucuronosyltransferase 1A1 (UGT1A1) may be associated with hyperbilirubinaemia and it appears to be a risk factor for gallstone formation. Our aim was to detect the correlation between the UGT 1A1 (TA)n repeats and hyperbilirubinaemia and gall stone formation in Indian sickle cell patients. This was a cross-sectional study; which was carried in an autonomous tertiary care hospital. The study subjects were 50 sickle cell anaemia and 70 sickle cell β-thalassaemia patients who were diagnosed by HPLC. The haemogram of the patients was measured by using an automated cell analyzer, while the serum bilrubin measurement was done by using a Beckman- CX-9 auto analyzer. The presence of gall stones was detected by ultra sound examination. ANOVA and the T-test were applied to compare the means of the groups. The allele frequencies were calculated according to the Hardy-Weinberg equilibrium. The allele, 7/7 TA of the UGT1A1 genotype was more frequent in the sickle cell patients and it was associated with hyperbilirubinaemia and gall stone formation. The allele, 7/7 TA of the UGT1A1 polymorphism affects the bilirubin levels and the development of gallbladder stone in the Indian sickle cell patients.