Use of Molecular Probes in RFLP - Restriction Fragment Length Polymorphism - When genomic DNAs from each of several individuals belonging to one or more species are digested separately with restriction enzymes, electrophoresed, blotted on a membrane, and probed with a labelled DNA clone, polymorphism in the hybridization pattern is sometimes revealed and attributed to sequence differences between the individuals.

Such variation has been termed as "restriction fragment length polymorphism" (RFLP). Variation in one DNA fragment obtained with a specific enzyme is treated as one RFLP.