Cumulative data show that the CFTR-dependent chloride efflux in MNCs was significantly increased at 6 (0.0130 ± 0.0019 ∆(F/F0)/min) and 12 months (0.0126 ± 0.0015 ∆(F/F0)/min) post-treatment, although still being lower than observed in non-CF MNCs (0.0187 ± 0.0022 ∆(F/F0)/min, n = 6). This evidence concerns the gene CFTR and cystic fibrosis.