How is cystic fibrosis different from that of a normal allele?

Cystic fibrosis (CF) is caused by mutations in the CFTR gene, which results in the production of a faulty cystic fibrosis transmembrane conductance regulator protein. This defective protein disrupts the transport of chloride ions across cell membranes, leading to thick, sticky mucus buildup in various organs, particularly the lungs and digestive system. In contrast, a normal allele of the CFTR gene produces a functional protein that maintains proper ion balance and mucus consistency, preventing the complications associated with CF. Thus, the primary difference lies in the functional capacity of the CFTR protein produced by the normal versus mutated alleles.