Since each VNTR region consists of repeats of a specific sequence of bases, complementary oligonucleotides can be synthesized.  These oligonucleotides, when labeled with a marker such as P³² or a chemiluminescent compound, are known as probes. 

There are five basic steps to developing DNA profiles using VNTRs:

1. Extracting DNA
2. Cutting DNA into fragments using restriction enzymes
3. Separating the fragments based on size using gel electrophoresis
4. Transferring the fragments to a nylon membrane (southern blotting), causing immobilization
5. Locating and identifying the fragments by applying a solution containing the probe of interest, which then hybridizes to the immobilized DNA. Visualization of the fragments requires a lengthy exposure of the probe to a detection system and can add several days to the assay time.

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