Question

If only one bond is broken in the sugar-phosphate backbone, it is called as ___________

(a) gap

(b) nick

(c) break

(d) leakage

This question was posed to me during an interview.

This key question is from Categories of Ligation Reaction in division Basics of Genetic Engineering of Genetic Engineering

Answer 1

The correct answer is (b) nick

To elaborate: In the case, if only one bond is broken in the sugar phosphate backbone, it is termed as nick. If a number of nucleotides are missing, it is termed a gap. Nick can be sealed by ligation reactions but gap can’t be sealed by a ligation reaction.