What Is It?
DNA fingerprinting (also known as DNA typing, DNA profiling, or genetic fingerprinting) is a person’s unique identifier, apart from
identical twins. It is a scientific technique based on making a profile of specific portions of an individual's DNA to establish identity, for example in paternity or maternity cases or in criminal investigations where biological material is left at a crime scene. Although the majority (99.5%) of our DNA is the same, there are short pieces, called microsatellites, which repeat many times in a person’s DNA. It's the pattern of repeats that are different between individuals. Knowing these microsatellite DNA sequences is the basis of DNA profiling. Let’s examine what are the main benefits of DNA fingerprinting.
Benefits in Paternity Tests
The sections of DNA used in DNA fingerprinting (as with all DNA) are passed down from parents to children. By comparing large numbers of these DNA microsatellites it is possible to establish with a high degree of certainty the paternity, maternity or both of a child.In some cases men or women need to gain peace of mind regarding their relationship to a child. A mother may have had sexual encounters with more than one man and does not know which one is the parent of her child. In other cases men may suspect the child is not his so may use DNA profiling as a way of being completely sure. Adopted children may want to know who their biological parents are. DNA testing may allow them to advance in this regard.
Also, DNA profiling could assist mothers seeking payment of alimony by a father who refuses to pay it saying he is not the child’s father. Or some people may use DNA fingerprinting to establish a link to grandparents to collect an inheritance or to claim social security benefits.
Benefits in Forensics
Another important use of DNA fingerprinting lies in the area of forensics as a tool for use in criminal justice cases. This type of benefit has gained much attention because of high profile murder cases that are solved with DNA evidence and because of the popularization of TV series with criminal investigations based on medical or scientific evidence.
Since DNA is contained in almost every cell, any tiny part of a person's body may be used to identify them. It may be a tiny piece of hair or a small drop of blood. These can be used to identify a victim (for example a person who has been murdered and fingerprints burned) or a criminal (as in rape cases where male body fluid left in a victim’s body can be used to identify the perpetrator).
The technology has also been successfully used to exonerate the innocent. For example, the first use of DNA fingerprinting in criminology was in 1986 and it was used to demonstrate that a man, Richard Buckland, who had been accused of murdering two schoolgirls could not have committed the crimes.
Benefits in Agriculture and Other Areas
Although this technology is mainly used in forensics and paternity tests, there are many other areas where it is being successfully applied.
In agriculture DNA fingerprinting is increasingly being used for variety identification–that is, to know if a seed is really from the variety being claimed. Also, genetic profiling is utilized to detect genetically modified organisms in agriculture. More specifically, markers have been used for characterization and determination of genetic diversity of tea to find genetic relatedness. Interestingly, and with the advent of herbal preparations and alternative medicine, DNA fingerprinting of herbal preparations could be useful in herbal origin authentication, and for the various claims of medical uses related to some of these plants.
In animals where lineage is important (race horses, dogs, etc) DNA fingerprinting can be used for parentage testing, and to help identify and breed thoroughbred horses for example. Although DNA fingerprinting is not failure-proof it has a high rate of success. Some legal questions may exist regarding the conclusiveness of certain DNA profiling but overall it is a highly secure technique.
Fridell, R. 2001. DNA fingerprinting: the ultimate identity. Franklin Watts Pub.
Weising, K. 2005. DNA fingerprinting in plants: principles, methods, and applications. CRC Press.