What genetic mutation causes cystic fibrosis?

Cystic fibrosis is a genetic disorder that affects the body's ability to produce mucus, sweat, and digestive juices. The disease is caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This gene is responsible for producing the CFTR protein, which is essential to the function of cells in the lungs, pancreas, liver, and intestines. The CFTR protein helps control the movement of chloride ions across cell membranes. When there is a mutation in the CFTR gene, it causes the chloride channels to not work properly, which leads to the build up of thick, sticky mucus in the lungs and pancreas. This mucus blocks the airways and can lead to lung infections and difficulty breathing, as well as digestive issues. This mutation can also cause the sweat glands to produce an abnormally high amount of salt, and the liver to not produce enough of the digestive enzyme bile acids. The exact cause of the mutation in the CFTR gene is still unknown, but it is believed to be inherited in an autosomal recessive manner, meaning that both parents must carry the mutated gene for the child to be affected.