Increased numbers of CAG repeats in the exon of a gene is associated with certain diseases. In a specific gene, the existing CAG
codons are in the 'zero' reading frame, in- frame with the AUG initiation codon. The effect of increased numbers of CAG repeats on the encoded protein is:___________. a. to silence of the gene to generate a truncated protein b. to generate a protein with a run of consecutive glutamines c. to generate a frameshifted protein product d. none of the above
The correct answer is - option b. to generate a protein with a run of consecutive glutamines.
Explanation:
The initiation code AUG is the code for methionine and as well as the initiation code for the particular protein or peptide chain. In this protein, there is a repeat of CAG is increased with the initiation code so, even though they are in zero reading frame they code for their amino acid which is glutamine.
So. an increased number of CAG repeats will result in a protein with the a run of consecutive glutamines.
