Molecular Pathology- Miscellaneous I
Question No. 8. The Answer is: (A) A 3-bp deletion.
Discussion: There are over 1300 different mutations in the cystic fibrosis transductance receptor (CFTR) gene. Most of these are single point mutations. There are missense, frameshift, splice-site, nonsense and deletion mutations. The DF508 mutation is due to an in-frame 3-bp deletion and accounts for approximately 70% of all mutations in CFTR. It is present at a carrier rate of 1:20 in Caucasians.