A conservative missense mutation results in

A conservative missense mutation results in

• A. An amino acid with different properties
• B. The same codon
• C. A frameshift
• D. An amino acid with similar properties

Answer: (D)

A conservative missense mutation substitutes one amino acid for another that has similar chemical properties (such as size and hydrophobicity). Because the new amino acid behaves similarly in the protein, the overall structure and function are often preserved, making this a milder change than a non-conservative switch. This is why the best description is an amino acid with similar properties. It’s not the same codon—missense changes code for a different amino acid, not the same one—so it isn’t a silent mutation. It also isn’t a frameshift, which would come from insertions or deletions that shift the reading frame. A change to an amino acid with different properties would be non-conservative and more likely to disrupt function.

A conservative missense mutation substitutes one amino acid for another that has similar chemical properties (such as size and hydrophobicity). Because the new amino acid behaves similarly in the protein, the overall structure and function are often preserved, making this a milder change than a non-conservative switch. This is why the best description is an amino acid with similar properties. It’s not the same codon—missense changes code for a different amino acid, not the same one—so it isn’t a silent mutation. It also isn’t a frameshift, which would come from insertions or deletions that shift the reading frame. A change to an amino acid with different properties would be non-conservative and more likely to disrupt function.