Practice question

Restriction mapping relies on systematic cleavage with single enzymes and combinations, followed by agarose gel electrophoresis to measure fragment sizes accurately. By overlapping patterns from single and double digests, distances between recognition sequences can be ordered around a circle, producing a circular map with relative positions. Ethidium bromide staining only visualizes DNA without mapping, Southern blot detects specific sequences after digestion, and PCR amplifies regions but does not locate sites. Only deliberate restriction digestion provides positional information about cleavage sites essential for cloning design, subcloning, and RFLP analysis in molecular biology.