Cystic Fibrosis

Written by Abdullah Tarique

Cystic fibrosis (CF) is an aggressive life-limiting autosomal recessive disease with a high rate of mortality. Mutation in the cystic fibrosis conductance regulator (CFTR) gene is the sole origin of CF. CFTR gene encodes a protein that functions cAMP-activated chloride (Cl-) channel. Mutation in CFTR gene leads to less or no production of CFTR protein that results in the defective or reduced transport of Cl- and bicarbonate (HCO3-) ions in multiple organs. Organs affected due to mutation include gut, lungs, liver, pancreas and reproductive organs, however, the lungs are mostly affected organs. CF lung disease is characterized by the accumulation of viscous mucus, chronic inflammation, and persistent bacterial infections in the lungs. The thick, viscous mucus leads to clogging in the respiratory linings resulting in stuffy nose, wheezing and breathlessness. Persistent infection-directed inflammation leads to permanent structural damages of the respiratory linings that eventually results in respiratory failure and death. CF is highly prevalent among the Caucasian population from developed countries including UK, Europe, North America and Australasia. Until 2005, the life expectancy of patients with CF was around 28 years, however, with the advancement of diagnosis and treatment, the median survival time of patients with CF increased to 37 years over the past decade.

Clinical Features



Cellular Characteristics





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Cystic Fibrosis worldwide:

Gene mutation leading to cystic fibrosis

Six different classes of mutation according to effects on CFTR protein


Median survival time of CF patients