What is RFLP?
RFLP stands for “Restriction Fragment Length Polymorphism.” It is a molecular biology technique that produces a pattern of bands that resembles a bar code. For any isolate of Mycobacterium bovis, this pattern is a characteristic “fingerprint” which serves as an indicator of whether or not there is a relationship with other strains of M. bovis. Figure 1 shows a DNA “fingerprint” of M. bovis. Note its resemblance to a barcode. How is DNA “fingerprinting” by RFLP performed? Figure 2 provides a schematic diagram of the steps involved in producing a RFLP “fingerprint.” Step 1. In addition to regions that are used specifically to code for the production of various proteins, the genetic material of all M. bovis isolates contain pieces of DNA referred to as “insertion sequences” (open boxes). Isolates of M. bovis may be distinguished by the number of copies of these insertion sequences and their location within the chromosome. Two insertion sequences are detected by this procedure: IS6110 and
