Describe the Process of Genetic Fingerprinting.

Genetic Fingerprinting. It has been found in research that sections of DNA which do not code for part of a gene contains highly repetitive sequences of bases. These are called Variable Number Tandem Repeats, {VNTR's}. A genetic fingerprint is a method of revealing the differences in size of VNTR's between individuals. Firstly a DNA sample is extracted from the cell. Restriction enzymes then cut sections of the DNA close to but not within the VNTR …

…by capillary motion. The DNA fragments are then denatured by heating to give single stranded DNA. A radioactive isotope of phosphorus with a base sequence identical to one of the VNTR sequences is used to locate the particular bands. This is also known as a DNA probe and it binds to its complementary single stranded DNA. Any excess probe is washed off. The probes are accurately located by placing X-ray film over the nylon membrane.