Going to patients with one or both unidentified mutations, we did not identify peculiar variants within the 3′UTR CFTR region with the exception of the rs1042180, causing an C>T change at the 4575+1251 nucleotide in the 3′ UTR region, that was found in a large percentage of alleles from either CF and CFTR-RD patients and control subjects. This evidence concerns the gene CFTR and cystic fibrosis.