A Paradigm-Shift in Molecular Therapy of Cystic Fibrosis? Gene Therapy versus Pharmacological Correction of Protein Function

Since the early 1990ies Cystic Fibrosis (CF), an autosomal-recessive disease due to mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene and its protein product, is seen as one of the main disease-targets for gene therapy . About 2000 different CF-causing gene-mutations have been identified. Some mutations are particularly common in certain populations, most notably a trinucleotide deletion called DeltaF508, which is observed in 70-80% of the CF-alleles in Caucasians. The presently most pursued gene therapy strategy for autosomal recessive diseases such as CF aims at introducing a functional copy of the mutated gene into the affected cells of the patient. This gene sequence should then provide sufficient non-mutated protein as required for normal cell function. This strategy has the great advantage that it should work for any kind of CFTR-mutation, irrespective of its exact sequence.