DNA Fingerprinting / DNA Typing/ DNA Profiling
In 1984, British geneticist Alec Jeffreys, developed the technique of DNA fingerprinting when he noticed certain DNA sequences (called minisatellites) which do not contribute to the functionality of the gene repeat within the gene. It was determined that a unique pattern of these is present in each organism and it was the conclusion of Jeffreys that multiple individuals from a single zygote (e.g., identical twins) was the only exemption for this.
How does DNA fingerprinting work?
In DNA fingerprinting, there is the use of a specific type of DNA sequence known as a microsatellite, for identification purposes. Short pieces of DNA known as microsatellites repeat many times in a given person’s DNA. A vast majority of DNA regions called loci of one human being will match exactly that of any other human, making distinguishing between two people rather difficult. However, it is virtually impossible to match all of the loci and the odds of two people having the same DNA is about 50 billion to 1.
More details about DNA fingerprinting
In children, DNA sections used are passed down from parents and despite the fact that all the sections are not necessarily passed on, no child has pairs that their parents have not passed on and maternity or paternity may be determined by comparing large groups of these sections.
Sections of the DNA are present in every piece of the body, every cell, blood drop, skin follicle or strand of hair. DNA fingerprinting may use any of these and this is especially important since all physical traces of the presence of a person are almost impossible to eradicate and this is what forensic professionals capitalize on. In past cases also, despite the body being disfigured etc, DNA fingerprinting is possible by using the teeth and other features to procure a cell for identifying the person.
Uses of DNA fingerprinting
- Individual Identification – has been a blessing in fields like forensics and crime investigation etc.
- Fighting Fraud – DNA fingerprinting can provide the kind of conclusive evidence required to uncover fraud.
- Uncovering Inherited Diseases – the ability to predict the possibility of diseases in the progeny of those with diseases is possible.
- Mapping Genography – used by the national geographic society, to determine the migration pattern of using some genetic markers of human beings. These are unchanged while being passed down through the generations and this is what the professionals look for.
- The Shoah Project – aiming to build a database along genetic lines of the victims of the holocaust, the reason primarily is the reunification of families separated during the holocaust.
- The Murder of the Last Tzar of Russia – following the Russian revolution by the Bolsheviks around 1917 identified Nicholas Romanov’s and his family’s remains by making use of DNA finger printing.
- The Remains of the September 11th – used prominently for the identification of the remains of victims of 9/11. Instrumental was the national institute of justices in identifying more than 20,000 victims.