Question

What would happen, if in a gene encoding a polypeptide of 50 amino acids, ${25}^{th}$ codon (UAU) is mutated to UAA?

• A. A polypeptide of 49 amino acids will be formed
• B. A polypeptide of 25 amino acids will be formed
• C. A polypeptide of 24 amino acids will be formed
• D. Two polypeptides of 24 and 25 amino acids will be formed

Answer 1

The correct option is C A polypeptide of 24 amino acids will be formed

Mutation of 25${}^{th}$codon (UAU) to a stop codon (UAA) would cause premature termination of polypeptide chain as UAA does not code for any amino acid. This would create a polypeptide of 24 amino acids.

So, the correct answer is 'A polypeptide of 24 amino acids will be formed'