What is a mutation?

What is a mutation?

• A. A change in the protein's amino acid sequence after translation.
• B. A change in the DNA sequence that can alter gene function or regulation.
• C. The process of converting RNA back into DNA.
• D. The RNA sequence that codes for a protein.

Answer: (B)

Mutation is a change in the DNA sequence that can alter gene function or regulation. DNA carries the instructions for making proteins and for controlling when and where those proteins are produced, so a change in the sequence can affect the amino acid sequence of a protein or the ways a gene is expressed. Some mutations change protein function or expression levels, while others may have little or no effect. The other statements describe processes or molecules that are not mutations: altering a protein after it’s made is a post-translational modification, reverse transcription is RNA-to-DNA copying, and an RNA sequence is not a mutation in DNA.

Mutation is a change in the DNA sequence that can alter gene function or regulation. DNA carries the instructions for making proteins and for controlling when and where those proteins are produced, so a change in the sequence can affect the amino acid sequence of a protein or the ways a gene is expressed. Some mutations change protein function or expression levels, while others may have little or no effect. The other statements describe processes or molecules that are not mutations: altering a protein after it’s made is a post-translational modification, reverse transcription is RNA-to-DNA copying, and an RNA sequence is not a mutation in DNA.