Mutations of the cationic trypsinogen gene in hereditary and non-hereditary pancreatitis.

BACKGROUND/AIMS: Mutations in the cationic trypsinogen gene have been detected in patients with hereditary pancreatitis (HP). This study investigates the prevalence of the R122H, N29I, A16V and -28delTCC mutations in the common, non-hereditary forms of chronic pancreatitis and in a HP family. METHODS: DNA was prepared from blood samples of 53 patients with chronic pancreatitis (36 alcoholic, 14 idiopathic and 3 hereditary), 20 alcoholic controls and 20 healthy, ethnically matched controls. The R122H and A16V mutations were identified by the polymerase chain reaction (PCR) and restriction enzyme digestion. A nested-PCR was used to identify the N29I mutation. The -28delTCC deletion and the C133807T polymorphism were sought by direct sequencing. RESULTS: The R122H mutation was detected in 1 patient with alcoholic chronic pancreatitis and all 3 affected members of a HP family. The N29I, A16V and -28delTCC mutations were not detected in any of the study subjects. At the C133807T polymorphism, the C allele and C/C genotype were significantly increased in alcoholic chronic pancreatitis (p = 0.001 and p = 0.0004, respectively) while the T allele and CT genotype were significantly reduced (p = 0.001 and p = 0.004, respectively) compared to healthy controls. CONCLUSIONS: Mutations of the cationic trypsinogen gene are rarely found in chronic pancreatitis patients of typical aetiology. Screening for these mutations should be considered in those with a family history consistent with hereditary pancreatitis but may also be appropriate in a well-defined subgroup of patients with non-hereditary chronic pancreatitis, i.e. those who have developed the disease before the age of 30.

Mutations of the cationic trypsinogen gene in patients with hereditary pancreatitis.

BACKGROUND: Hereditary pancreatitis has been shown to be caused by one of two mutations (R117H and N21I) of the cationic trypsinogen gene (PRSS1). Families with hereditary pancreatitis in the north of England were investigated for these mutations. The clinical features associated with each mutation were compared. METHODS: In individuals from nine families with hereditary pancreatitis, DNA was screened for the R117H and N21I mutations. All five exons of the cationic trypsinogen gene were also sequenced to search for additional mutations. Haplotype analysis was carried out to identify common ancestors. Clinical data were collected. RESULTS: The R117H mutation was identified in three families and N21I in a further five. The R117H mutation was associated with a more severe phenotype than N21I in terms of mean(s.d.) age of onset of symptoms (8.4(7.2) versus 16. 5(7.1) years; P = 0.007) and requirement for surgical intervention (eight of 12 versus four of 17 patients respectively; P = 0.029). Haplotype analysis suggested that each mutation had arisen more than once. CONCLUSION: Two mutations in the cationic trypsinogen gene cause hereditary pancreatitis in eight of nine families originating in this region. The R117H mutation is associated with a more severe form of the disease in terms of age at onset of symptoms and requirement for surgical intervention.