Genetic Testing

DNA profiling, as we know it today, was developed thanks to two independent breakthroughs in molecular biology that occurred at the same time on different sides of the Atlantic. In the USA the polymerase chain reaction  was invented by Kary Mullis, while in the UK 'DNA fingerprinting' was being discovered by Professor Sir Alec Jeffreys at the University of Leicester.In its earliest incarnation this technique was performed by restriction of 0.5–10μg extracted DNA using the restriction enzyme HinFI, followed by Southern blotting hybridisation designed to bind to multiple 'minisatellites' present in the restricted DNA.This multi-locus probing  technique would result in probes binding to multiple independent DNA fragments at the same time giving rise to the traditional 'bar-code' pattern that is often visualised when we think of forensic DNA analysis, even today. Differences in the number of times the probe sequence is repeated in each DNA fragment forms the basis of the individual patterns observed on the autoradiogram image.  (Citation 4)     

 

                                                                                             Uses of DNA profiling

Uses of DNA profiling Include :

 

Paternity - to find out if the alleged father is actually the biological father of the child.

Twins - identical twins share the same genetic material, while fraternal (non identical) twins develop from two eggs fertilised by two sperm and are no more alike than individual siblings born at different times. It can be difficult to tell at birth whether twins are identical or fraternal.

Siblings - for example, adopted people may want to have DNA tests to make sure that alleged biological siblings are actually their blood brothers or sisters.

Immigration - some visa applications may depend on proof of relatedness.

Criminal justice - DNA testing can help solve crimes by comparing the DNA profiles of suspects to offender samples.  DNA profiles are kept on a database.