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.

Genetics of Pancreatitis: Are There Differences between Korea and Other Countries? / 대한췌담도학회지

In the initial genetic studies about pancreatitis in Korea, gene mutations were thought to be rare. However, the recent findings of PRSS1, SPINK1, and CFTR mutations in patients with idiopathic chronic pancreatitis or inherited cases of chronic pancreatitis are much more common than originally predicted. Therefore, it is important to identify underlying genetic background in idiopathic chronic pancreatitis to avoid progression and development of complications. In addition, concentrated and strict follow-up must be given to the patients because of very high risk of pancreatic cancer. However, it is also true that studies about genetics in pancreatitis were not enough to compare with Western studies. Accordingly, further large scale studies are necessary to find other unknown possible genes that could be related to the chronic and hereditary pancreatitis.

Multisite Heterozygous Mutations of PRSS1 Gene and Clinical Characterization of Patients With Hereditary Pancreatitis in The Chinese / 生物化学与生物物理进展

In four patients with chronic pancreatitis from two hereditary pancreatitis (HP) families and 63 normal controls, five exons of cationic trypsinogen gene (PRSS1) were amplified by PCR and it's products were analyzed by sequencing, related clinical data were also collected. All the four patients were found mutations in the PRSS1 gene but their clinical feature is absolutely different. Six patients with diabetes mellitus were found in pedigree No. 1, it's members show pancreatitis symptom later, at about 29, the tumor markers (CA19-9, CA72-4) is obviously higher than the patients in pedigree No. 2, two patients with chronic pancreatitis in pedigree No. 2, show symptom earlier without diabetes mellitus, their clinical characterization are different too. The number of CD4+T cell/CD8+T is very low in Ⅲ 8, but Ⅲ 7 is normal, and the level of anti-HBs of Ⅲ 8 is variable in the course of pancreatitis, but the phenomenon was not found in Ⅲ 7. In their PRSS1 gene two guanosine (G) to adenosine (A) mutations were found in PRSS1 exon 3 of pedigree No. 1, one was detected at 336 basyl, the other mutation occurs at 361 basyl. The results of the mutations were Lys →Lys and Ala →Thr. While thymine (T) to adenosine (A) and (guanosine) G→(adenosine) A mutation in PRSS1 exon 3 was detected in the other patient of pedigree No. 2 (Ⅲ 8). One was 361 basyl, the other at 415 basyl. While c.415 T→A was not found in the proband of pedigree No. 2 PRSS1 gene (Ⅲ 7). All of the mutations were heterozygous mutation, that is to say all of the trypsinogen were wild type and mutant type concomitance, the normal and abnormal pathway of active trypsinogen exist partially. At the same time, the mutations of SPINK1 were not observed. Compared with the documents and registration of NCBI, it can be concluded that PRSS1 gene had many kinds of mutations in hereditary pancreatitis, the heterozygous mutations (c.336 G→A, c.415 T→A) were the novel mutations and related with clinical phenotype. What's more, it's the first time that the multisite heterozygous mutations of PRSS1 gene were reported. The presence of the mutations in four patients with chronic pancreatitis, it's absence in their relatives and the strong evolutionary conservation of the mutation, all indicate that the trypsinogen mutation is associated with hereditary pancreatitis and for the first time raises the question whether a gain or a loss of trypsin function participates in the onset of Chinese pancreatitis.

Hereditary Pancreatitis / 대한소화기학회지

Hereditary pancreatitis (HP) is an autosomal dominant inherited disease characterized by recurrent episodes of pancreatitis often beginning in childhood, a family history of at least 2 other affected members, and the absence of known etiologic factors. The discovery of mutations in cationic trypsinogen gene (PRSS1) in HP not only provided insights into the molecular mechanisms of pancreatitis, but also opened a new era in the field of chronic pancreatitis. The detection of mutations in serine protease inhibitor, Kazal type 1 (SPINK1) and CFTR in patients with hereditary or idiopathic chronic pancreatitis has placed the emphasis on the importance of genetic mutations in pancreatitis. Because the estimated cumulative risk of pancreatic cancer developement in hereditary pancreatitis is nearly 40%, screening tests are important in selected cases. There are no specific medical therapies recommended in patients with HP. Registration of patients with Nationwise Registries is essential if management strategies are to be improved and genetic research to be continued.