Which of the following mutations could potentially lead to a nonfunctional protein?

Which of the following mutations could potentially lead to a nonfunctional protein?

• A. Silent mutation
• B. Nonsense mutation
• C. Point mutation
• D. Insertion mutation

Answer: (B)

A nonsense mutation is a change in the nucleotide sequence of a gene that results in the creation of a premature stop codon. This early termination of translation means that the protein will be truncated, leading to a nonfunctional protein being produced. Because this mutation severely disrupts the normal length and structure of the protein, it typically results in a complete loss of function. In contrast, silent mutations do not change the amino acid sequence of the protein, while point mutations and insertions can have various effects depending on their specific nature and location within the gene. Point mutations can lead to synonymous changes or missense mutations, which may or may not alter protein function. Similarly, insertion mutations could lead to frameshifts, but their effect on protein functionality can vary. However, it is the nonsense mutation that most directly guarantees a nonfunctional protein due to the introduction of a stop signal in the reading frame.

A nonsense mutation is a change in the nucleotide sequence of a gene that results in the creation of a premature stop codon. This early termination of translation means that the protein will be truncated, leading to a nonfunctional protein being produced. Because this mutation severely disrupts the normal length and structure of the protein, it typically results in a complete loss of function.

In contrast, silent mutations do not change the amino acid sequence of the protein, while point mutations and insertions can have various effects depending on their specific nature and location within the gene. Point mutations can lead to synonymous changes or missense mutations, which may or may not alter protein function. Similarly, insertion mutations could lead to frameshifts, but their effect on protein functionality can vary. However, it is the nonsense mutation that most directly guarantees a nonfunctional protein due to the introduction of a stop signal in the reading frame.