Q. Out of A-T, G-C pairing, bases of DNA may exist in alternate valency stage owing to arrangement called :
(a) Tautomerisational mutation
(b) Analogue substitution
(c) Point mutation
(d) Frameshift mutation
Solution :
Correct option : B
1) Analogue substitution: Base analogues are molecules that can substitute for normal bases in nucleic acids. Usually, substitution of a base analogue will result in altered base pairings and structural changes that affect DNA replication and transcription of genes.
2) Tautomerization mutation means the shifting in the bases of DNA. For example, a Guanine goes through a tautomeric shift to its rare enol form (G*) when it opts for the replication process. 3) A frameshift mutation is a mutation caused by the addition or deletion of a base pair or base pairs in the DNA of a gene resulting in the translation of the genetic code in an unnatural reading frame from the position of the mutation to the end of the gene. 4) Point mutation: a mutation affecting only one or very few nucleotides in a gene sequence.
So, the correct answer is ‘Tautomerisational mutation’.
