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Cystic fibrosis (CF) is one of the most common genetic disorders. CF is inherited as an autosomal recessive trait and a defective gene causes the body to produce an abnormal amount of very thick, sticky mucus which clogs the lungs and pancreas, interfering with breathing and digestion. This mucus builds up in the breathing passages in the lungs and the pancreas and respiratory complications develop from the blockage of the bronchial passages. Eventually, the cilia which are responsible for clearing the mucus are destroyed. In addition, the mucus traps bacteria which cause infections and permanent damage to the lungs, and may also block the ducts of the pancreas which contains enzymes necessary for the digestion of food.