Rank the following mutations with respect to their likelihood of affecting the structure of the polypeptide (from most likely to affect structure to least likely).
1) insertion mutation in the middle of an intron
2) deletion of 3 bases crossing an intron-exon border
3) substitution mutation at the third position of a codon
4) substitution mutation at the second position of a codon
A) 1, 2, 4, 3
B) 2, 3, 4, 1
C) 3, 4, 2, 1
D) 4, 3, 2, 1

Question

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2) A deletion of 3 bases crossing an intron-exon border can remove or add amino acids and potentially disrupt the reading frame, significantly affecting the structure. 3) A substitution at the third position of a codon might not change the amino acid due to the degeneracy of the genetic code, but it can still affect the structure if it changes the amino acid. 4) A substitution at the second position of a codon is more likely to change the amino acid, affecting the structure. 1) An insertion in an intron is least likely to affect the structure since introns are removed during RNA splicing.

Rank the Following Mutations with Respect to Their Likelihood of Affecting