ABSTRACT
Objective:To explore the polymorphism of the uridine diphosphateglucuronosyl transferase 1A1 ( UGT1A1) gene in children of multiple nationalities with etiology-unknown neonatal hyperbilirubinemia in Qiubei County. Methods:Full-term neonates with unknown cause hyperbilirubinemia were collected.They were admitted to neonatal ward of Qiubei People′s Hospital from September 2017 to June 2018.All of them were performed UGT1A1 gene test. Results:A total of 100 neonates were enrolled in this study.Among them, 53 infants were Han, and others were minorities.Ten mutation sites of UGT1A1 gene were found.Five sites were never reported before and 4 sites could be pathogenic mutations.In addition, c.211G>A.was the most common genetic mutation, and 13 cases of homozygote and 32 cases of heterozygote were revealed by exome sequencing.The bilirubin levels of children with homozygote c. 211G>A were higher than those without the variation in this study and the differences were statistically significant ( t=2.621, P=0.008). The incidence of c. 211G>A mutation was similar between Han and minority nationalities.Among new-found mutations, c.1091C>CA heterozygous mutation was found in 19 children and in several nationalities, suggesting that this was a common UGT1A1 gene mutation in Qiubei County.Besides c. 211G>A and c. 1091C>CA were the most common variants.The incidence of c. 211G>A had no significant difference between Han and minority nationalities (χ 2=0.215, P=0.643). Neither had the incidence difference of c. 1091C>CA between Han and minority nationalities (χ 2=0.017, P=0.897). Conclusion:c. 211G>A and c. 1091C>CA mutations , which are distributed in both Han and minority nationalities, are common UGT1A1 mutations in Qiubei County.The distribution rate of c. 211G>A mutation is high in the population.The homozygous variation of c. 211G>A is associated with neonatal hyperbilirubinemia.