The Science of DNA Fingerprinting: Present, Past and Future

Author Name(s): Anand Bajpai
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DNA fingerprinting also called DNA Typing in genetics is the method of isolating and making images of sequences of DNA (deoxyribonucleic acid). The technique was developed in 1984 by the British geneticist Alec Jeffrey’s, after he noticed the existence of certain sequences of DNA (called mini satellites) that do not contribute to the function of a gene but are repeated within the gene and in other genes of a DNA sample. Jeffrey’s also determined that each organism has a unique pattern of these mini satellites, the only exception being multiple individuals from a single zygote (e.g., identical twins). The chemical structure of everyone’s DNA is the same. The only difference between people (or any animal) is the order of the base pairs. There are so many millions of base pairs in each person’s DNA that every person has a different sequence. Using these sequences, every person could be identified solely by the sequence of their base pairs. However, because there are so many millions of base pairs, the task would be very time-consuming. Instead, scientists are able to use a shorter method, because of repeating patterns in DNA. These patterns do not, however, give an individual “fingerprint,” but they are able to determine whether two DNA samples are from the same person, related people, or non-related people. Scientists use a small number of sequences of DNA that are known to vary among individuals a great deal, and analyze those to get a certain probability of a match.


The characteristics of all living organisms, including humans, are essentially determined by information contained within DNA that they inherit from their parents. The molecular structure of DNA can be imagined as a zipper with each tooth represented by one of four letters (A, C, G, or T), and with opposite teeth forming one of two pairs, either A-T or G-C. The letters A, C, G, and T stand for adenine, cytosine, guanine, and thymine, the basic building blocks of DNA. The information contained in DNA is determined primarily by the sequence of letters along the zipper. For example, the sequence ACGCT represents different information than the sequence AGTCC in the same way that the word “POST” has a different meaning from “STOP” or “POTS,” even though they use the same letters. The traits of a human being are the result of information contained in the DNA code.


From the above facts which are based on secondary data, it was known that the DNA Fingerprinting is very crucial and important factor in criminology. It has also an important role in Human society and health. A problem is only with the feasibility in terms of 100% assurance. It leaves many doubts in its result as the result can not be assured. Its future prospects are very bright because it can control over the illegal offences. Presently it is playing a role of dynamism.
An early use of DNA fingerprinting was in legal disputes, notably to help solve crimes and determine paternity. The technique was challenged, however, over concerns about sample contamination, faulty preparation procedures, and erroneous interpretation of the results. Efforts were made to improve its reliability, and today the technique has been refined through the use of more-specific and more-sensitive probes and better blotting membranes.

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