What is the significance of the genetic code being degenerate?

• A. All amino acids are encoded by a single codon.
• B. It reduces transcription fidelity.
• C. Most amino acids are encoded by multiple codons, providing redundancy that reduces the impact of some mutations and allows silent changes.
• D. It prevents mutations entirely.

Answer: (C)

Degeneracy means the genetic code uses multiple codons to specify the same amino acid. This redundancy helps protect proteins from genetic changes: many single-nucleotide mutations in the DNA don’t alter the amino acid that gets built into the protein, so the resulting protein sequence stays the same—these are silent mutations. The third base of a codon often has flexibility (wobble), so different nucleotides can still encode the same amino acid, further buffering the impact of mutations. This buffering is the major significance: it provides robustness to the genome and reduces the likelihood that a random DNA change will disrupt protein sequence.

Some amino acids do have unique codons, so not every codon change is harmless, and the code doesn’t prevent mutations entirely, nor is it a property of transcription fidelity.