Around 1500 mutations and 300 polymorphisms in the CFTR gene are known (Cystic Fibrosis Mutation Database; http://www.genet.sickkids.on.ca/cftr/), usually grouped in five classes representative of all the possible alterations in the maturation process and/or transfer of the CFTR protein [1], [5]. Here, CFTR is linked to cystic fibrosis.