Mutation screening for coding regions of PRSS1, SPINK1, CFTR and the new hereditary pancreatitis-associated chymotrypsin C (CTRC) genes showed a novel variation, c.541A > G (p.S181G), in the exon 4 of PRSS1 gene and the classical CF p.F508del mutation in the CFTR. Both mutations were present in his clinically normal mother and absent in the patient's father. The gene discussed is CTRC; the disease is cystic fibrosis.