The basic technique for the detection of RFLPs involves fragmenting a sample of DNA with the application of a [[restriction enzyme]], which can selectively cleave a DNA molecule wherever a short, [[recognition sequence|specific]] [[nucleic acid sequence|sequence]] is recognized in a process known as a [[restriction digest]]. The DNA fragments produced by the digest are then separated by length through a process known as [[agarose gel electrophoresis]] and transferred to a membrane via the [[Southern blot]] procedure. [[Nucleic acid hybridization|Hybridization]] of the membrane to a labeled [[Hybridization probe|DNA probe]] then determines the length of the fragments which are [[Complementarity (molecular biology)|complementary]] to the probe. A restriction fragment length polymorphism is said to occur when the length of a detected fragment varies between individuals, indicating non-identical sequence homologies. Each fragment length is considered an [[allele]], whether it actually contains a [[coding DNA|coding region]] or not, and can be used in subsequent genetic analysis.
[[File:RFLPDemo1.gif|right|thumb|450px|Schematic for RFLP by cleavage site loss]]
[[File:RFLP genotyping.gif|right|thumb|360px|Analysis and inheritance of allelic RFLP fragments (NIH)]]
