In the coding region, natural selection tends to eliminate all of the mutations because of the high importance these regions have. The coding region contains genes that synthesize proteins and the changes in the DNA sequence can have devastating effects on the cell. Therefore, there are very few differences in the sequences of coding regions that can help us trace the lineage.
On the other hand, in the non-coding regions, the mutations often accumulate because they have little effect on the cell and the adaptive value of the organism. This enables us to trace up the lineage by comparing the sequences and seeing the differences in the sequences.
Answer:
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.