Genetic counseling for hereditary pancreatitis--the role of molecular genetics testing for the cationic trypsinogen gene, cystic fibrosis and serine protease inhibitor Kazal type 1.

The importance of pretest information, using an accredited DNA laboratory and interpreting the genotype on behalf of the patient and their physicians is emphasized. Care with predictive testing and the strong encouragement to involve a specialist genetic counseling service is made. A similar approach to genetic testing should be used when children are involved. Because of the incomplete pickup of PRSS1 mutations, particularly of a limited mutation panel of R122H and N291 (perhaps with A16V), a diagnosis of HP cannot be ruled out by molecular genetic testing alone. The A16V mutation has a reduced penetrance, and its contribution to pancreatitis remains unclear. The advice to patients with genetic forms of pancreatitis is a strong encouragement to avoid smoking, to avoid alcohol, and to remain in contact with clinical and research groups for their follow-up and screening trials for early pancreatic cancer. The remaining issues are of how wide to cast the net of investigation in patients with unexplained pancreatitis, particularly looking for mutations in the CFTR and lower penetrance genes such as PSTI/SPINK1.