DNA fingerprinting is a process through which the unique genetic code of a person is identified and codified. DNA fingerprint is called so because just like the technology of fingerprint became very popular in the 1930s as means of crime detection, beginning in the 80s, DNA testing achieved a similar level of popularity in forensic science.
Though fingerprints can be changed through surgical means or may be tampered with, the DNA code of every individual is completely unique and it therefore serves as a distinct marker of a person or evidence of his/her presence at a certain place. Even very small amounts of body fluids like sweat, mucus, blood and semen that the criminal inadvertently leaves behind on the scene of the crime can be later traced, and successfully reveal his/her identity conclusively, since DNA is present uniformly in each cell of an individual’s body. Thus, forensic DNA fingerprinting has become extremely popular as a method of crime detection. However, this method can also be used for medical purposes like detecting and predicting the chances of rare hereditary diseases that can be passed on from parents to their unborn children as well as in newborn babies.
DNA fingerprinting is also extremely useful in research and development of cures for genetic disorders, as it helps locate and isolate the genetic patterns that cause certain diseases in particular families or racial groups, and thereby eventually shows the way to curing the condition. In addition, maintaining official records of the DNA fingerprints of each citizen in a state can help identify missing persons and casualties of accidents, as well as serve as a device of personal identification in important commercial transactions.
The DNA fingerprinting process is an elaborate one that can be conducted only in a laboratory. It involves six steps. First of all, the DNA sample must be extracted, for which purpose even a tiny strand of hair or a piece of skin suffices. Second, the DNA is treated with various enzymes that work as biological sieves to cut and sort out the DNA strands according to their sizes. Third, this sample is placed on a thin nylon sheet and soaked overnight. Next, the nylon sheet is 'probed' by being exposed to radioactive radiation, which makes each strand of the DNA to stick only to certain places on the sheet, revealing a specific, unique pattern. Lastly, a set of 5-10 such 'probe' samples are examined together to arrive at the DNA fingerprint.