Analysis of mutation site characteristics of Gilbert syndrome and Crigler--Najjar syndrome in relation to uridine diphosphate glucuronosyltransferase A1 gene

Abstract

Objective: To investigate the mutation characteristics and clinical relevance of Gilbert syndrome (GS) and Crigler-Najjar syndrome (CNS) in relation to uridine diphosphate glucuronosyltransferase A1 (UGT1A1) gene. Methods: The characteristics of UGT1A1 gene mutation and their clinical relevance were analyzed by searching PubMed and Human Gene Mutation Databases. Results: A total of 163 mutation sites were found in the UGT1A1 gene since November 16, 2018. The following patterns existed at the above sites: (1) the numbers of gene mutations occurring between different exons of UGT1A1 was related to GS or CNS phenotypes, and were positively correlated with the length of the exon; (2) nonsense point mutations was mainly occurred in type I of CNS; (3) GS, Crigler-Najjar syndrome type II compound heterozygous mutation sites had a certain combination and distribution, among which - 3279t > G mutation was found in all four GS complex heterozygous compositions; (4) UGT1A1 gene mutation sites reported in Asia had marked aggregation in c.211-c.558. Conclusion: UGT1A1 gene mutation characteristics and clinical relevance varies with different mutation sites, reporting areas and populations. This study has reference value for basic research and clinical diagnosis and treatment of GS and CNS.