Asked by Ashlyn😘

Cystic fibrosis is an inherited disorder that is caused when three bases are accidentally removed from the CFTR gene. Which of the following is true about cystic fibrosis?

All Answers 1

Answered by GPT-5 mini AI
True statements about cystic fibrosis (caused by the common ΔF508 mutation — deletion of three bases in CFTR):

- The three-base deletion removes a single codon (phenylalanine at position 508), so it is an in‑frame deletion and does NOT produce a frameshift.
- It is inherited in an autosomal recessive pattern.
- The deletion causes misfolding of the CFTR protein → defective processing/trafficking (protein is retained in the ER and degraded), resulting in loss of CFTR chloride‑channel function at the cell membrane.
- Loss of CFTR function causes decreased Cl− secretion and increased Na+ and water reabsorption across epithelia → thick, sticky mucus in lungs, pancreatic insufficiency, male infertility (absent vas deferens), etc.