What is the main cause of cystic fibrosis?

The main cause of cystic fibrosis is a genetic mutation in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is responsible for controlling the movement of salt and water in and out of cells. When this gene is mutated, it leads to the production of thick, sticky mucus that affects the lungs, digestive tract, and other organs.

The mutation in the CFTR gene is inherited from both parents. It is a recessive gene, meaning both parents must pass it on for a child to have cystic fibrosis. If a child inherits the mutated gene from only one parent, they will be a carrier of the disease but will not have symptoms.

The CFTR gene mutation is responsible for the majority of cystic fibrosis cases. However, there are other rare forms of the disease that are caused by mutations in other genes. These mutations are much less common and are not as well understood.