Related Sites Of Susceptibility Genes For Primary Biliary Cholangitis

Objective:Primary biliary cholangitis(PBC)was a complex disease with multiple genes.Genome-wide association analysis(GWAS)of European population found that IL12A was a susceptible gene for PBC,but lacked the corresponding functional analysis.Therefore,we selected IL12A gene as one of the candidate genes in this study.In addition,HELZ2,ARID3A,LYN,IL12RB2,MYC-PVT1,Has-MiR-1206 and TNFSF15 were also selected.The purpose of this study was to carry out a comprehensive study of candidate genes for PBC and the gene function analysis in Chinese Han population.Methods:A total of 586 PBC patients and 726 healthy controls were included in this study.The single nucleotide polymorphism(SNP)loci of IL12A,HELZ2,LYN,ARID3A,IL12RB2,MYC,PVT1,Has-MiR-1206 and TNFSF15 genes were genotyped by matrix-assisted laser desorption ionic time-of-flight mass spectrometry(MALDI-TOF-MS).PLINK software was used for statistical analysis.The loci associated with IL12A gene were analyzed by eQTL.At the same time,we earried out luciferase reporting experiments using HEK293 cells for the relevant regions.In the whole genome,we performed chromosome conformation capture sequencing and chromatin immunoprecipitation experiments on peripheral blood mononuclear cells(PBMC)from a patient with PBC.Results:Three SNP loci in the 22 labeled SNPs of IL12A gene were associated with PBC in Chinese Han population.The strongest SNPs were rs4679868(p=6.59E-05)and rs6441286(p=8.00E-05).Luciferase reporter assay showed that this region can regulate gene expression and had enhancer activity.Through eQTL analysis,we found that there was a significant correlation between IL12A expression and IL12A expression in Chinese Han population(p<0.01).The rare missense mutation of HELZ2,LYN were associated with PBC.IL12RB2,MYC-PVT1,Has-microRNA-1206,TNFSF15 were not associated with PBC in Chinese Han population.In addition,we found that there was the strongest chromatin interaction located in the HLA region.Conclusions:IL12A was associated with PBC in Chinese Han population.SNPs associated with PBC in Han population were potential cis-eQTL elements.These high-risk alleles of SNP were significantly associated with the decrease of IL12A expression in lymphoblastic cell lines of Chinese Han population.Missense mutation sites of HELZ2 and LYN genes were associated with PBC in Chinese Han population.IL12RB2,MYC-PVC1,Has-MiR-1206 and TNFSF15 genes were not susceptible to PBC in Chinese Han population.The region of HLA-DRB1/HLA-DQA1 was a super-enhancer.