What gene mutation is primarily involved in cystic fibrosis?

The mutation primarily involved in cystic fibrosis is found in the CFTR gene, which encodes for a chloride channel protein. This gene plays a crucial role in regulating the movement of chloride ions across epithelial cell membranes, affecting mucus production, sweat production, and other bodily secretions. When mutations occur in the CFTR gene, the function of this chloride channel is disrupted, leading to the accumulation of thick, sticky mucus in various organs, particularly the lungs and pancreas. This accumulation can cause respiratory problems and digestive issues characteristic of cystic fibrosis.

Other genes mentioned, such as BRCA1, TP53, and HBB, are associated with different diseases. BRCA1 mutations are primarily linked to hereditary breast and ovarian cancer, TP53 mutations are involved in a variety of cancers due to its role in regulating the cell cycle and preventing tumor formation, and HBB mutations are related to sickle cell disease and beta-thalassemia. Thus, the CFTR gene is specifically the one that, when mutated, causes cystic fibrosis.