Explore whether molecular defects and transcriptional alterations in the genes encoding for ENaC subunits (SCNN1A, B, and G genes), possibly associated to CFTR gene mutations, could be the cause of CF and CF-like disease. To this purpose, the SCNN1A, SCNN1B, SCNN1G genes are analysed at mutational and transcriptional control level, including biological and functional analysis.