From Wikipedia, the free encyclopedia.
Restriction fragment length polymorphism (or RFLP) is a property of DNA used in molecular biology methods, for example, genetic fingerprinting or paternity testing.
Method
Usually, DNA from an individual organism is first amplified (multiple copies are made) by the polymerase chain reaction (PCR). It is then chopped into restriction fragments by endonuclueases, which only cut where there are DNA sequences recognized by the enzymes . The restriction fragments are then separated according to length by agarose gel electrophoresis. The resulting gel may be enhanced by Southern blotting.Result
The distance between the locations cut by restriction enzymes (the restriction sites) varies between individuals: so the length of the fragments varies, and the position of certain gel bands differs between individuals (thus polymorphism). This can be used to genetically tell individuals apart. It can also show the genetic relationship between individuals, because children inherit genetic elements from their parents. It is also used to deterimne the relationships among species.
- See also: genetics -- retroposon
