30 1) Blood sample. 2) DNA is extracted from blood cells 1) Blood sample. 2) DNA is extracted from blood cells. 3) DNA is cut into fragments by a restriction enzyme. 4) The DNA fragments are separated into bands during electrophoresis in an agarose gel. 5) The DNA band pattern in the gel is transferred to a nylon membrane. 6) Radioactive DNA probe, designed to recognise specific DNA sequences, is prepared. 7) Probe DNA binds to the specific DNA sequences on the membrane. 8) Excess DNA is washed off, but the DNA pattern is invisible at this stage. 9) X-ray film is placed next to the membrane & exposed to the radioactive DNA. 10) The developed X-ray shows the pattern of DNA bands
49 DNA fingerprinting in Argentina to establish kinship of the 'disappeared', the children, often born in captivity, of parents kidnapped and assassinated by the former military regime there. Here a geneticist uses a multi-channel pipette to prepare samples for the process. A bank of blood samples, taken from all the potential relatives, provides the DNA for comparison with that from the child in question. Fragments of DNA are seperated into bands by electrophoresis in an agarose gel. Every human being produces a unique pattern of DNA bands, hence its potential as a kind of genetic
54 Ian Wilmut and Dolly. In 1996, British embryologist Professor Ian Wilmut created, the world's first sheep cloned from an adult sheep cell. The research was conducted at the Roslin Institute in Edinburgh, Scotland.