Cell membrane

, Airways

Mucus-clogged bronchi and bronchioles. Respiratory infections. (Common)


Blocked small bile ducts impair digestion. (Rare)


Blocked ducts prevent release of digestive enzymes, impairing fat digestion. Diabetes is possible. (Common)


Hard stools may block intestines. (Rare)

Reproductive tract

Absence of vas deferens. (Common)


Salty sweat. (Common)

Cystic fibrosis transmembrane conductance regulator (CFTR) protein


From gene to protein to person. (a) The gene encoding the CFTR protein, and causing cystic fibrosis when mutant, is on the seventh largest chromosome. CFTR protein folds into a channel that regulates the flow of chloride ions into and out of cells lining the respiratory tract, pancreas, intestines, and elsewhere. (b) In cystic fibrosis, the CFTR protein is abnormal, usually missing an amino acid. Its shape is altered, which entraps the chloride ions inside cells. Water entering these cells leaves behind very thick mucus and other secretions in the places highlighted in the illustration. The sticky secretions cause the symptoms of the illness.

Source: Data from M.C. lannuzi and F.S. Collins, "Reverse Genetics and Cystic Fibrosis" in American Journal of Respiratory Cellular and Molecular Biology, 2:309-316, 1990.

Was this article helpful?

0 0
Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

Get My Free Ebook

Post a comment