A missense mutation in the middle of the first exon of the CFTR gene leads to cystic fibrosis. Which of the following could be a reason why this mutation causes the disease? The mutation leads to lower amounts of mRNA (or no mRNA) The mutation leads to a misfolded protein that is targeted for degradation The mutation leads to a shorter mRNA The mutation leads to a truncated protein Solution Cystic fibrosis transmembrane conductance regulator (CFTR) is ABC transporter protein involved in the transfer of chloride ions across cell membranes of epithelial membranes. The mutation in the production of functional CFTR protein leads to cystic fibrosis, that causes respiratory infections. The mutation produces misfolded protein which is more susceptible for degradation. Therefore, option 2 is correct: The mutation leads tomisfoldedprotein that is targeted for degradation..

1. A missense mutation in the middle of the first exon of the CFTR gene leads to cystic fibrosis.
Which of the following could be a reason why this mutation causes the disease? The mutation
leads to lower amounts of mRNA (or no mRNA) The mutation leads to a misfolded protein that
is targeted for degradation The mutation leads to a shorter mRNA The mutation leads to a
truncated protein
Solution
Cystic fibrosis transmembrane conductance regulator (CFTR) is ABC transporter protein
involved in the transfer of chloride ions across cell membranes of epithelial membranes. The
mutation in the production of functional CFTR protein leads to cystic fibrosis, that causes
respiratory infections. The mutation produces misfolded protein which is more susceptible for
degradation.
Therefore, option 2 is correct: The mutation leads tomisfoldedprotein that is targeted for
degradation.