PRSS1, SPINK1, CFTR, and CTRC Pathogenic Variants in Korean Patients With Idiopathic Pancreatitis

BACKGROUND: This study aimed to identify pathogenic variants of PRSS1, SPINK1, CFTR, and CTRC genes in Korean patients with idiopathic pancreatitis. METHODS: The study population consisted of 116 Korean subjects (65 males, 51 females; mean age, 30.4 yr, range, 1-88 yr) diagnosed with idiopathic chronic pancreatitis (ICP), idiopathic recurrent acute pancreatitis (IRAP), or idiopathic acute pancreatitis (IAP). We analyzed sequences of targeted regions in the PRSS1, SPINK1, CFTR, and CTRC genes, copy numbers of PRSS1 and SPINK1, and clinical data from medical records. RESULTS: We identified three types of pathogenic PRSS1 variants in 11 patients, including p.N29I (n=1), p.R122H (n=1), and p.G208A (n=9). Sixteen patients exhibited heterozygous pathogenic variants of SPINK1, including c.194+2T>C (n=12), p.N34S (n=3), and a novel pathogenic splicing variation c.194+1G>A. A heterozygous CFTR p.Q1352H pathogenic variant was detected in eight patients. One patient carried a heterozygous CTRC p.P249L pathogenic variant, which is a known high-risk variant for pancreatitis. All patients had normal PRSS1 and SPINK1 gene copy numbers. Weight loss occurred more frequently in patients carrying the p.G208A pathogenic variant, while pancreatic duct stones occurred more frequently in patients with the c.194+2T>C pathogenic variant. CONCLUSIONS: Pathogenic variants of PRSS1, SPINK1, and CFTR were associated with idiopathic pancreatitis, while pathogenic variants of CTRC were not. Copy number variations of PRSS1 and SPINK1 were not detected.

Hereditary Pancreatitis / 대한소화기학회지

The first family of hereditary pancreatitis was described in 1952. The mode of inheritance is autosomal dominant trait with an 80% of penetrance rate. Although hereditary pancreatitis is rare, this disorder has provided valuable insights in understanding the pathophysiology of pancreatitis and pancreatic cancer. The causative gene of hereditary pancreatitis was identified in 1996 through mutational analysis of genes within chromosome 7q35. Most forms of hereditary pancreatitis are caused by one of two common mutations, R122H in the third exon or N29I in the second exon of the cationic trypsinogen gene (protease serine 1, PRSS1). R122H mutation is the most common PRSS1 mutation. Additional mutations of the cationic trypsinogen gene have been described. In Korea, first family of hereditary pancreatitis with cationic trypsinogen gene mutation revealed an arginine to histidine amino acid substitution at the residue 122. Patients with hereditary pancreatitis present with symptoms at an early age and have significant risk for the development of chronic pancreatitis and pancreatic cancer. The risk of pancreatic cancer is estimated to be 53-fold higher after the age of 50 years than the general population. The risk of pancreatic cancer is not related to the type of mutation. Since hereditary pancreatitis is a strong risk factor for pancreatic cancer, it is important to establish a diagnostic criteria for diagnosis and surveillance. However, there are potential benefits, risks and limitations in genetic testing for hereditary pancreatitis. It is difficult to provide the proper treatment, but recent developments in therapeutic approaches may be helpful in caring hereditary pancreatitis. This article includes the current status, pathogenesis, clinical features, and management of hereditary pancreatitis including the aspects of pancreatic cancer.

Mutations of SPINK1 and PRSS1 Gene in Korean Patients with Chronic Pancreatitis / 대한소화기학회지

BACKGROUND/AIMS: It has been found that mutations of cationic trypsinogen gene (PRSS1) and serine protease inhibitor, Kazal type 1 gene (SPINK1) increase the susceptibility of chronic pancreatitis (CP). Specifically, mutations in the PRSS1 gene are related to the occurrences of hereditary and idiopathic pancreatitis while SPINK1 mutations are known to act as a disease modifier and are associated with idiopathic CP. However, the association of SPINK1 mutations with alcoholic CP is still controversial. We investigated the prevalence of PRSS1 and SPINK1 mutations in idiopathic and alcoholic CP in Korea. METHODS: Seventy-one Korean patients with CP (alcoholic: 47, idiopathic: 22 and familial: 2) and 19 controls were included in this studies. Genomic DNA was extracted from peripheral blood of the patients. Mutations of SPINK1 (exon 3: N34S) and PRSS1 (exon 2: N29I, exon 3: R122H) genes were detected by PCR-RFLP methods. For the detection of SPINK1 mutation, restriction endonuclease PstI and BsrDI were used, while Sau3A and AflIII were used for the defection of PRSS1 mutation. RESUTLS: Only one patient (2.1%) with alcoholic CP was a heterozygote for SPINK1 (N34S) mutation. Mutation in the PRSS1 (N29I, R122H) gene was not found in any group of CP patients. Additionally, we could not find any mutations of SPINK1 or PRSS1 in the control group. CONCLUSIONS: SPINK1 and PRSS1 mutations are not related to the development of CP in Korea.

Cationic Trypsinogen Gene Mutation in Patients with Chronic Idiopathic Pancreatitis / 대한소화기학회지

BACKGROUND/AIMS: Mutation of Cationic trypsinogen gene is clearly associated with hereditary pancreatitis and plays an important role in the pathogenesis of pancreatitis. According to literature, this mutation is occasionally occurred in patients with pancreatitis in Western countries and Japan. The aim of this study was to find out whether the mutation was observed in Korean patients with chronic idiopathic pancreatitis. METHODS: Peripheral blood samples of 11 patients with chronic idiopathic pancreatitis were collected consecutively, and DNA was extracted from the samples. Polymerase chain reaction was performed in exon 2 and 3 of cationic trypsinogen gene. Then, DNA products were purified and sequenced. RESULTS: The mutation was not found in exon 2 and 3 of cationic trypsinogen gene in these patients. CONCLUSIONS: There was no cationic trypsinogen mutation in Korean patients with chronic idiopathic pancreatitis. Further large sampled cohort study is needed.