Question

In a mRNA, the codons are read linearly and each codon consists of three consecutive nucleotides which code for one amino acid. During a deletion mutation, a deletion of three consecutive bases in the coding region of a gene cannot result in one of the following.

• A. Deletion of a single amino acid without any other change in the protein.
• B. Replacement of two adjacent amino acids by a single amino acid.
• C. Replacement of a single amino acid by another without any other change in sequence of the protein.
• D. Production of a truncated (shorter) protein.

Answer 1

Answer: (C)

Replacement of a single amino acid by another without any other change in sequence of the protein.

In an mRNA, there are codons which are composed of the three nucleotides and they code for one amino acid. If there is a deletion of three consecutive nucleotides. This can result in the deletion of the single amino acid in the protein. There can be the replacement if a new amino acid in place of two neighboring amino acids. The replacement of the single amino acid with other will not take place as there is deletion and not the substitution. There is production of a short protein with loss of one amino acid.

Thus, the correct answer is option C