Mutations associated with misfolding, ER stress, and chronic pancreatitis have been described in the serine protease 1 (PRSS1) gene that encodes human cationic trypsinogen6–8, the carboxypeptidase A1 (CPA1) gene9,10, the carboxyl ester lipase (CEL) gene11–16, the pancreatic lipase (PNLIP) gene17–21, and the chymotrypsin C (CTRC) gene22,23. Here, PRSS1 is linked to chronic pancreatitis.