Identify the degenerate codon from the following:

The correct answer is Option (4) → GUU, GUG, GUA

A degenerate codon refers to codons that code for the same amino acid. In the genetic code, multiple codons can code for a single amino acid, which is known as codon degeneracy.

Analysis of the options:

CCU, CAU, CGU:

• CCU codes for proline.
• CAU codes for histidine.
• CGU codes for arginine.
• These codons do not code for the same amino acid, so this is not a degenerate set.

UUG, UCG, UAG:

• UUG codes for leucine.
• UCG codes for serine.
• UAG is a stop codon.
• These codons code for different things, so this is not a degenerate set.

AUU, ACU, AAU:

• AUU codes for isoleucine.
• ACU codes for threonine.
• AAU codes for asparagine.
• These codons code for different amino acids, so this is not a degenerate set.

GUU, GUG, GUA:

• All three codons (GUU, GUG, GUA) code for valine.
• This is an example of a degenerate set because multiple codons code for the same amino acid.