CF Etiology: Loss of CFTR protein activity leads to cystic fibrosis
Loss of CFTR protein activity is the underlying cause of cystic fibrosis (CF). Individual CFTR mutations can lead to decreased quantity or function (and sometimes both) of CFTR proteins at the epithelial cell surface. These defects in CFTR proteins limit ion transport through the apical cell membrane.1,2
Defective ion transport in the lungs, pancreas, gastrointestinal (GI) system, sinuses, skin, and reproductive system leads to the symptoms of CF. The resulting imbalance of fluid and electrolytes causes thick, sticky mucus (in lungs, sinuses) or viscous secretions (in pancreas, GI tract, reproductive tract) to accumulate, which interferes with the proper function of these organs. Defective chloride ion transport in the sweat gland leads to high salt concentration in sweat, but does not impact the morphology of the gland.1-5
Underlying cause of CF
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