cystic fibrosis

[Craig Webster]

In article: <4gdjsr$mqc at ns2.ryerson.ca>  nmarsden at acs.ryerson.ca (Neil 
Marsden - CABC/W95) writes:
> 
> Shane (wegfn08 at ucl.ac.uk) wrote:
> : from wegfn08 at ucl.ac.uk
> : I am a first year biology student and need info  on cystic fibrosis 
> : and sweat glands and carrier proteins and the  ions necessary for 
> :  reabsorbtion any help would be a great help
> : thanks 
> : shane Lynch
> 
Apparently the CFTR protein represents some sort of transmembrane ion 
channel that has a sort of "ball and chain" configuration, with the "ball" 
fitting neatly into the ion channel to stop ion flux. Energy is required to 
move this "ball" and allow ions to flow. This is provided by two ATPase 
sites on the protein (I think).

The mutations that cause CF are numerous and there is evidence that there is 
a variation in the severity of CF (e.g. pancreatic involvement/ no 
pancreatic involvment) depending on which mutation is causing the disease. 
Mutations that disrupt the ATPase sites cause the most severe disease whilst 
mutations that affect the "ball" the least severe disease.

For diagnosis of the disease a test called the sweat test is usually 
performed. This involves collecting the sweat and measuring the amount of 
sodium and chloride. A raised chloride (> 50 mmol) is indicative of cystic 
fibrosis. Genetic diagnosis is also now avaliable. Most centres can also 
carrier screen for the most common mutations (e.g. delta 508)

I hope this is right, I'm just trying to remember a lecture I attended some 
months ago so I'd check  the above !

I hope this helps and that someone will correct any mistakes I have made. 
 
-- 
Craig Webster              |  Tel: 01245 442700
Grade B Clinical Biochemist|  Fax: 01245 514077
Broomfield Hospital        |  email (work) cwebster at broombio.demon.co.uk
Chelmsford, CM1 5ET        |        (home) cwebster at bimbo.demon.co.uk