Study For UGT1A1 Polymorphism Associated With Post-hepatitis Hyperbilirubinemia

Objective:Up to now,there is no unified understanding of the pathogenesis of posthepatitis hyperbilirubinemia,There are also different opinions on whether and how to treat it.In this study,through retrospective analysis of patients with post-hepatitis hyperbilirubinemia,the relationship between post-hepatitis hyperbilirubinemia and the polymorphism of UDP-glucuronosyltransferase1A1(UGT1A1)gene was preliminarily identified,and its pathogenesis was discussed to provide certain reference value for clinical diagnosis and treatment.Methods:Blood samples were collected from 177 patients with hepatitis,including 87 patients with post-hepatitis hyperbilirubinemia as the experimental group and 90 patients with normal liver function with viral hepatitis as the control group(the difference between the two was the presence of hyperbilirubinemia).Sanger sequencing,tests the polymorphism of five exons、three promoters { TATA box 、distal Element(DE)and proximal element(PE)} and one phenobarbital-responsive enhancer module(PBREM)of UGT1A1 gene;SPSS 22.0 software was used to compare the difference in genotype frequency between the experimental group and the control group;The UGT1A1 enzyme activity corresponding to the corresponding genotype combination was calculated to determine the relationship between post-hepatitis hyperbilirubinemia and Gilbert syndrome(GS);Hardy-Weinberg balance test(H-W test)and linkage unbalance analysis(L-D analysis)were conducted by using haploview 4.1 software;The Regulome DB and haploreg websites are used to predict the function of SNP sites in non-coding regions of genes.Results:1.There were statistically differences between the experimental group and the control group in the frequencies of UGT1A1*60,UGT1A1*112,UGT1A1*28,UGT1A1*6 and g.16761A>C(P<0.05),Among them,UGT1A1*28,UGT1A1*6,UGT1A1*60 and UGT1A1*112 showed significant statistical difference(P<0.01).2.There is complete linkage unbalance between UGT1A1*60 and UGT1A1*112,and partial linkage unbalance between them and UGT1A1*28 respectively.3.UGT1A1 enzyme activity < 40% of normal people was used as the diagnostic criteria for GS,and the difference between the experimental group and the control group was statistically significant.About 1/3 patients in the post-hepatitis hyperbilirubinemia group met the diagnostic criteria for GS.4.There is a negative correlation between UGT1A1 enzyme activity and bilirubin levels,There is a statistical difference in bilirubin levels between the dual wild-type and dual heterozygous mutation combinations of UGT1A1 * 6 and UGT1A1 * 28.5.Using Regulome DB to predict the relationship between UGT1A1 * 112 and transcriptional regulation: score=0.55436,rank=1f;Using Haplo Reg to predict the functional domain of transcription factors binding to DNA,it was found that UGT1A1 * 112 has 6 motifs.Conclusion:About 1/3 of the patients with post-hepatitis hyperbilirubinemia had GS combined with chronic hepatitis.There is a negative correlation between UGT1A1 enzyme activity and bilirubin levels,and the combination of UGT1A1 * 6 and UGT1A1* 28 double heterozygous mutations can elevate bilirubin levels.UGT1A1*112 May be e QTL+ TF binding/ Dnase peak.