Question

What would happen if 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. A polypeptide of 50 amino acids will be formed.
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Hint:

A premature stop codon (UAA) halts translation, producing a truncated protein.

Answer 1

The Correct Option is C

The codon UAA is a stop codon. Mutation of the 25\textsuperscript{th} codon from UAU (which codes for tyrosine) to UAA will terminate translation prematurely, resulting in only 24 amino acids being formed.