It is the most common serious genetic disease in the world, and is characterized by a genetic defect that leads to an abnormal function of the CFTR protein: (Cystic fibrosis transmembrane conductance regulator), a protein involved in the transmembrane transport of salts. As a result of an altered ion transport into the cell, cystic fibrosis is manifested by an alteration of the epithelial cells of the bronchial secretions, breasts, pancreas, intestine, bile duct and the sweat glands.
Patients who are suffering from this disease have inherited the mutated CFTR gene from both parents. It is estimated that in Italy the carriers of the genetic defect on the CFTR protein are about 2.5 million.
A healthy carrier of the genetic defect has no clinical evidence and leads a perfectly normal life. If, in a couple, both people are carriers of the genetic defect there is one chance out of four (25%) of having a child with cystic fibrosis. The disease affects both males and females equally. The same couple has a 50% chance of having a healthy child, but carrier and a 25% chance of having a healthy child and not a carrier of the defect.