Question

The gene that controls the rate of mutation of another gene is
A. Regulator gene
B. Inducer gene
C. Mutable gene
D. Mutator gene

Answer 1

Hint: The rate of mutation refers to the probability that a unit length of DNA, generally a base pair, mutates with time. Rates of mutations are controlled by certain genes that control the process of mutation upto some extent.

Complete Answer:
Mutations are changes in the nucleotide sequence of DNA. Such changes can be confined to one base pair or involve multiple base pairs including deletion, addition, amplification and recombination. Genes can be classified into several types. They are regulator genes, inducer genes, operator genes, promoter genes, mutator genes, etc.
1. Regulator Gene : These are the genes that control the transcription unit and thereby control the protein expressions.
2. Inducer Gene: These are the genes that induce the process of transcription. A particular inducer induces the whole process by inactivating all the inhibitors of the transcription.
3. Mutable gene: Some genes are highly unstable in nature and they can undergo mutation rapidly than the other genes. They are called the mutable genes.
4.Mutator Gene: These are the genes that can regulate the rate of mutation of other genes.

 Hence the correct answer is option D.

Note: A gene mutation is a permanent alteration in the DNA sequence that makes up a gene, such that the sequence differs from what is found in most people. These are the sudden heritable changes. Change in the base pairs of the DNA by mutations can cause expression of a different phenotype by changing the amino acid sequence of the proteins.