Question

Following mutated sequence of mRNA shows _____ mutation.
Normal mRNA : AUG GUC GGA CUG GGC GUC UAA
Mutated mRNA : AUG GUC UGA CUG GGC GUC UAA

• A. Silent Mutation
• B. Missense Mutation
• C. Nonsense Mutation
• D. Frameshift Mutation

Answer 1

The correct option is C Nonsense Mutation

As $3^{rd}$ codon GGA is changed to UGA (Stop codon), Translation will stop resulting in a faulty protein. So it is a nonsense mutation. In a missense mutation, the substitution of a nucleotide results in incorporation of a new amino acid.
In frameshift mutation, the point mutation changes the reading frame of the template. Silent mutations do not show any effect on the final protein product.