The following questions refer to Figure 17.5, a table of codons.

Figure 17.5
-Which of the following mutations would be most likely to have a harmful effect on an organism?
A)a base-pair substitution
B)a deletion of three nucleotides near the middle of a gene
C)a single nucleotide deletion in the middle of an intron
D)a single nucleotide deletion near the end of the coding sequence
E)a single nucleotide insertion downstream of, and close to, the start of the coding sequence

Question

The following questions refer to Figure 17.5, a table of codons.
  
Figure 17.5
-Which of the following mutations would be most likely to have a harmful effect on an organism?
A)a base-pair substitution 
B)a deletion of three nucleotides near the middle of a gene 
C)a single nucleotide deletion in the middle of an intron 
D)a single nucleotide deletion near the end of the coding sequence 
E)a single nucleotide insertion downstream of, and close to, the start of the coding sequence

Quizplus · Accepted Answer

A single nucleotide insertion near the start of the coding sequence can cause a frameshift mutation, altering the reading frame and potentially leading to a nonfunctional protein.

The Following Questions Refer to Figure 17