INTRODUCTION
What is Cystic Fibrosis?
Normal and Affected Airway
Cystic fibrosis is a autosomal recessive genetic disorder that causes mucus to build up and clog some of the organs in the body, particularly the lungs and pancreas. When mucus clogs the lungs, it can make breathing very difficult. The thick mucus also causes bacteria to get stuck in the airways, which causes inflammation (or swelling) and infections that lead to lung damage. Mucus also can block the digestive tract and pancreas. The mucus stops digestive enzymes from getting to the intestines. The body needs these enzymes to break down food, which provides important nutrients to help people grow and stay healthy. People with cystic fibrosis often need to replace these enzymes with medicine they take with their meals and snacks, which helps them digest food and get proper nutrition.
Cystic fibrosis is a genetic disease. This means that people inherit it from their parents through genes or DNA. Genes, found in the nucleus of all the body's cells, control cell function by serving as the blueprint for the production of proteins. To have cystic fibrosis, a person must inherit two copies of the defective CFTR gene—one copy from each parent. If both parents are carriers of the CFTR gene (i.e., they each have one copy of the defective gene, but do not have the disease themselves), their child will have a 25% chance of inheriting both defective copies and having cystic fibrosis, a 50% chance of inheriting one defective copy and being a carrier, and a 25% chance of not having CF or carrying the gene.