Finger printing Have been used for nearly a hundred years to identify individuals since each individual has distinctive finger prints. This finding has been used frequently in crime detection.
However, the criminals too have come to know of it and now try to see that they leave no finger prints. therefore, the resent developments of a technique to identify individuals by comparing their DNA with the DNA isolated from a sample (just a drip is enough) of blood or semen or a hair (base) is revolutionizing the field of forensic investigations.
This technique, called southern blotting, provides DNA prints from the DNA of the suspect and the sample/s collected from the scene of the crime. Since no two individuals have identical DNA (except zygotic twins), this is a foolproof method to identify the criminals.
If the two DNA prints (one from the DNA of the suspect and the other from the DNA of the sample collected from the crime site) are identical, it undoubtedly proves that the suspect has committed the crime.
At the prints are like finger prints and are used for similar purposes, the method is often referred to as DNA finger printing.
The technique can also be used to settle paternity disputes with much certainty in contrast to the blood grouping evidence which could not provide definite evidence as so many individuals have the same blood groups.