One of the most common hazardous genetic (inherited) diseases, cystic fibrosis affects the exocrine glands and is characterized by the production of abnormal secretions, leading to abnormally viscous mucus build-up.

This accumulation of mucus can impair the pancreas and, secondarily, the intestine. Mucous build-up in lungs tends progressively to impair respiration.

Without treatment, CF results in death for 95% of affected children before the age of five.