The Relationship Between N34S Gene Mutation Of SPINK1and Chronic Pancreatitis Of Different Types

Chronic pancreatitis (CP) is the sustained damage of pancreatic tissue and function caused by various reasons, compared with acute pancreatitis, characterized as permanent change and extensive fibrosis of the basic structure of pancreas. Chronic pancreatitis is a common disease in western countries, the incidence is relatively low in our country, but in recent years the incidence rate is rising. Being clear on the mechanism of chronic pancreatitis contributes to early diagnosis and treatment of chronic pancreatitis.Recent studies have found certain relationship between trypsinogen gene (PRSS-1) mutation, cystic fibrosis transmembrane conductance regulator gene (CFTR) mutation and the incidence of certain types of chronic pancreatitis, confirmed the gene polymorphism is a risk factor for the incidence of chronic pancreatitis.Objective In this study, through the analysis of serine protease inhibitor Kazal1(SPINKl) gene N34S mutation rate in chronic cholecystic pancreatitis, chronic alcoholic pancreatitis, chronic idiopathic pancreatitis and autoimmune pancreatitis patients, compare the gene mutation of each group with the control group, to discuss the influence of SPINK1gene mutation on susceptibility to different types of chronic pancreatitis, to make sure the gene mutation is a risk factor for the incidence of chronic pancreatitis, to study further the molecular mechanism of pathogenesis of chronic pancreatitis.Methods Informed and consent in patients with chronic pancreatitis,79cases of blood samples were collected from hospitalized patients diagnosed clearly during2010to2012year in Henan Provincial People’s Hospital, consists of27cases with chronic biliary pancreatitis,23cases with chronic alcoholic pancreatitis,24cases with chronic idiopathic pancreatitis,5cases with autoimmune pancreatitis.Blood samples were collected from60healthy controls at the same time.Extract genomic DNA, amplify, digest the SPINK1gene by PCR, and observe the polymorphism of DNA fragment, and next sequence the target gene of patient group and the control group respectively to observe the mutation.Results6cases of SPINK1N34S mutation was detected from139blood samples of the patient group and the control group, including4cases of24chronic idiopathic pancreatitis group,1case of27chronic biliary pancreatitis group,1case of23chronic alcoholic pancreatitis group, with incidence rate respectively16.7%,3.7%and4.3%. There was no case detected from chronic autoimmune pancreatitis group and the control group. The results of PCR-RFLP electrophoresis showed that the mutant gene produces a new restriction enzyme cutting sites because of the presence of mutations, so mutation gene was cut into two fragments of different size, new bands appeared on gel electrophoresis map. The mutations were sequenced both the patient cases and normal control,and gene mutations was found mutations in the SPINK1gene, A→G mutation group, two fluorescence bands appeared on the sequenced map of heterozygous strains.Conclusion On the whole, SPINK1N34S gene mutation rate of chronic pancreatitis patients group was7.6%, higher than that in healthy control group.From the view of different types of chronic pancreatitis, gene mutation rate of idiopathic pancreatitis compared with the normal control group was most significant.The mutation rate of patients with biliary pancreatitis, alcoholic pancreatitis and autoimmune pancreatitis had no statistical difference compared with the healthy control group.Significance In recent years, the mechanism of chronic pancreatitis was further studied by scholars at home and abroad,.Some mutations have been found,such as trypsinogen gene (PRSS-1) mutation, cystic fibrosis transmembrane conductance regulator gene (CFTR) mutation and serine protease inhibitor, Kazal type I (SPINK1) gene N34S mutation, to have certain relationship with the incidence of certain types of chronic pancreatitis.It was confirmed that the gene polymorphism was a risk factor for the incidence of chronic pancreatitis. Scholars in Europe and Japan study more in chronic idiopathic pancreatitis and chronic alcoholic pancreatitis, but study on chronic biliary pancreatitis accounted for the majority in China was few. In this study, the occurrence of serine protease inhibitor Kazal type Ⅰ (SPINK1) gene N34S mutation in our country as well as its correlation with the pathogenesis of chronic pancreatitis was further proved and discussed, especially for chronic biliary pancreatitis in China.The results showed that the incidence of chronic biliary pancreatitis was not statistically significantly related to SPINK1N34S gene mutation. This is the creative results of this research, which added further basis for the molecular mechanism of chronic pancreatitis.