Screening For CPA1 And PRSS1 Gene Mutation And Analysis Of Their Correlation With Chronic Pancreatitis

Chronic pancreatitis(CP)is a kind of substantial destruction of the pancreas,and ultimately may lead to pancreatic exocrine and endocrine dysfunction.The incidence of CP is low in China,but there is a clear upward trend in recent years.So clearing the pathogenesis of CP will contribute to the early diagnosis and treatment of it.With the development of the medical science,molecular biology and bioinformatics,some studies have shown that CP was caused by genetic and environmental factors,not a single gene disease.This study consists of two parts,one part is to screen the CPA1 and PRSS1 gene mutations in chronic pancreatitis and the other part explores the correlation of CPA1 and PRSS1 gene with chronic pancreatitis in the Han population of Sichuan province.We screened for CPA1 and PRSS1 gene and used the method of selecting TagSNPs in order to explore the association of CPA1 and PRSS1 polymorphisms with chronic pancreatitis in Chinese Han population of Sichuan province.Sequencing of the target fragment of the full exon regions of CPA1 and PRSS1 gene were carried out by Sanger direct sequencing method.The sequencing results were compared with the full-length cDNA of the target gene through the UCSC database to confirm the nature of the mutation(SNP or newly discovered mutations).We determined the reliability of the mutated sites through the SIFT website.Using the 1000-person genome project database to determine whether the mutation site is a new mutation The TagSNPs of the CPA1 and PRSS1 gene were selected by Haploview software.SNaPshot method to genotype above sites and SPSS software to calculate and analyze the genotype and allele frequencies.In the 192 cases of chronic pancreatitis,7 cases of CPA1 gene and PRSS1 gene mutation were found.The total mutation rate was 3.6%.3 cases have CPA1 gene mutation(1.6%,3/192),mutations were c.281A>G,c.370A>G and c.1074C>T.4 cases occurred PRSS1 gene mutation(2.1%,4/192),mutations were c.44C> T,c.182C>T,c.365G>A and c.486T>C.The CPA1 gene and PRSS1 gene mutation(0.5%,1/192)occurred in 1 case of CP.The above mutations were not found in the normal control group.In addition,we detected the rs537519042,rs1126899,rs559471767,rs782588903,rs34875501,rs745538166 and rs376671702 in two groups.All 5 SNPs(rs7811409,rs7790688,rs11560388,rs741487 and rs6667)have conformed to Hardy-Weinberg equilibrium(P>0.05).The AA allele and A allele frequencies of rs11560388 were 8.9%,4.2%,25.3% and 17.3% in the CP group and control group respectively(P<0.05).The GG allele and G allele frequencies of rs741487 were 31.8%,24.6%,55.5% and 46.5% in the CP group and control group respectively(P<0.05).The allele and genotype of rs7811409,rs7790688 and rs6667 had no significant difference between the CP group and control group(P>0.05).Further genetic model analysis showed that the risk of CP in rs11560388 A allele was 1.63 times more than that in G allele,while in the dominant model [(AG + AA)vs GG] and recessive model [AA vs(AG + GG)] were 1.63-fold and 2.23-fold higher in CP group than that of control group,respectively.In the risk of developing CP,rs741487 G allele carriers were 1.76 times as high as the C allele carriers.In the dominant model [(CG + GG)vs CC],the risk of CP group was 1.76 times the size of control group.In addition,rs7811409,rs7790688 and rs6667 were not associated with CP susceptibility(P>0.05).The mutations in CPA1 gene and PRSS1 gene were found in the Han population of Sichuan.These mutations may enrich the CPA1 gene and PRSS1 gene mutation spectrum.This is the first time to explore the correlation of CPA1 gene and PRSS1 gene and CP in the domestic.The rs11560388 and rs741487 loci of the CPA1 gene may be associated with chronic pancreatitis in Chinese Han population.