CFTR and cystic fibrosis: Similar to our group 3 with the 5T;12TG/VVCC genotype, Tosco et al. reported on 27 individuals (1 CF, 8 CFTR-RD, and 18 CFSPID), with one diagnosed as CF at the outset due to a positive SC test and bronchiectasis, and one CFSPID converting to CF (5.5%) due to a pathological SC test result (112 mEq/L) during the four years of follow-up [21].