Cystic fibrosis is a hereditary disease caused by a variety of mutations in the regulator of transmembrane conductance in cystic fibrosis (CFTR), that is located on chromosome 7. It has been described over a thousand mutations affecting the CFTR gene with different ways. The most common Cystic Fibrosis mutation is F508del, which is detected in approximately 54% of the individuals with Cystic Fibrosis in Greece.
In order to have the disorder, someone has to have two abnormal genes which are inherited from both parents who are carriers of the disease, without knowing it most of the times! If two carriers of the disease get married, the risk of delivering a baby with Cystic Fibrosis is a 1 in 4 or 25%.