CASR and cystic fibrosis: Going to the type of mutations in IPAT genes in the patients with CF and RP/CP: 2 were heterozygous for a splicing mutation in PRSS1 in cis, 4 patients were heterozygous for CTRC mutations, 3 patients were heterozygous for PRSS2 mutations, 2 patients were heterozygous for CASR mutations and 2 patients were heterozygous for KRT8 mutations; 1 patient had a splicing mutation in PRSS1 and a missense mutation in KRT8 (Table 2).