Defective protein production with premature termination of CFTR production. Class 1 mutations produce few or no functioning CFTR chloride channels.
Class 2 mutations
Defective trafficking of CFTR so that it does not reach the apical surface membrane where it can function.
Class 3 mutations
Defective regulation of CFTR even though it is able to reach the apical cell surface.
Class 4 mutations
CFTR reaches the apical surface but chloride transport through the channel is defective.
Class 5 mutations
Reduced production of functional CFTR. A small amount of functional CFTR may reach the surface.
So a couple of weeks ago I posted this article about a new and exciting drug which corrects the basic defect of one of the mutations of CF. The study was done on a mutation known as G551D. Well, mutation G551D falls into Class 3 of the mutation, the ones that have trouble regulating chloride. The new drug that should hit the market in later 2011 or early 2012 corrects this regulation problem, getting chloride in and out of the cells the way a normal persons would. Mutation R560T, one of Drew's mutation, also falls into Class 3. (I'll give you a moment to get excited if you can see where i'm going with this).....