The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single codon. What is the most likely result of this mutation in the protein product?

Answer: The most likely result is the production of abnormally sticky mucus that lined the walls of internal organs

Explanation:

The deletion occurring in cystic fibrosis, leads to a defect in the production of a protein called cystic fibrosis transmembrane conductance regulator. This protein functions in the production of body fluids like sweat, tears, and mucus digestive enzymes and saliva. In this production, the movement of chloride ions in and out of cells is important as it controls the movement of water that controls the thinning of the fluids to be produced.

In cystic fibrosis, there is a mutation in the control of production and movement of these chloride ions across cells, resulting also in a lack of movement of water.

This mutation results in the production of abnormally sticky and thick mucus, lining organs such as the lungs. This causes obstruction of secretory glands and airways.