Applications of Restriction Fragment Length Polymorphism

The availability of a variety of restriction endonuclease enzymes that cleave deoxyribonucleic acid (DNA) at specific sites has made it possible to identify the presence of polymorphic regions in the isolated fragments. Such restriction fragment length polymorphism (RFLP) results owing to a variation in the num ber of tandem repeats (VNTR) of a short DNA segment. These VNTR sequences can uniquely specify an individual and, as such, are used in DNA fingerprinting and in paternity testing. Restriction frag m ent length polymorphism may be found close to a disease gene, and, as such, can be used as a genetic disease marker. Certain criteria need to be fulfilled, however, for RFLP to be useful as a genetic disease marker, such as its closeness to the disease gene. Materials and methodology for detect ing RFLP are review ed with the current emphasis on amplification proce dures utilizing the polymerase chain reaction (PCR)