Genetic Fingerprinting

Developed by a British Geneticist Dr. Alec Jeffreys in 1984, genetic fingerprinting or DNA fingerprinting is defined as a method of isolating and distinguishing sequences of DNA from the DNA samples. Here are the details of the process of genetic fingerprinting and its applications:

Methods of Genetic Fingerprinting

Genetic fingerprinting is carried out using various methods, which are as follows:

• Restriction Fragment Length Polymorphism: This process is also called the Southern blot test. This method makes use of proteins called restriction enzymes to cut the DNA strands. The pieces of DNA are then separated using gel electrophoresis, a process that separated DNA strands based on their size and the corresponding negative charge that varies with the size. The DNA thus separated is transferred on to a nitrocellulose paper, which is then placed in the incubator so that DNA is permanently attached to the paper. This DNA is further analyzed using a radioactive probe. The variable number tandem repeats which are nothing but a short nucleotide sequence in the DNA, are unique for every person and hence this test helps to generate a DNA fingerprint of a particular person. A major disadvantage of this method is that it is very slow and requires a larger DNA sample.
• Polymerase Chain Reaction Polymerase Chain reaction is a very popular DNA fingerprinting method which includes amplification of specific portions of DNA using high temperature and thermostable polymerase enzyme with labeled DNA primers. Commercial PCR kits have made the process a very simple and easy method of DNA fingerprinting.
• Amplified Fragment Length Polymorphism This ia another popular method of genetic fingerprinting which scores over Restriction Fragment Length Polymorphism since it is far more time-effective. It makes use of polymerase chain reaction to amplify the DNA and focuses on the variable number tandem repeat to distinguish various DNA samples. The lower cost and the convenient operation and set up of this method makes it a popular method of genetic fingerprinting

Other popular techniques of DNA fingerprinting also includes the following methods:

• Y-chromosome analysis
• Mitochondrial Analysis

Applications of Genetic Fingerprinting

Genetic fingerprinting is used in various fields. Here are some of the applications of genetic fingerprinting:

Forensic Science: Genetic fingerprinting is widely applied in the field of forensic science. It is used to identify suspects by matching samples of blood, hair, saliva or semen at the crime scene and those of the suspects.

Paternity Testing: Genetic fingerprinting is also used in cases where the paternity has to be checked for in instances where the father refuses to own the child.

Organ Donors: Genetic fingerprinting is used to match DNA samples in case of organ donation as well. Fingerprinting ensures whether or not a particular organ donation would be safe by matching the DNA samples of the donor and the receiver.

Study of Animals: Genetic fingerprinting is also used while studying animals, especially large populations of wild animals. Genetic fingerprinting of DNA samples of animals also helps to identify closely related species of animals.

Prehistoric Studies: Genetic Fingerprinting has also been applied into the study of pre-historic times. It has been used to determine the genetic patterns of the population of pre-historic times.

Genetic fingerprinting is a vast field with a variety of applications in several areas. The study of DNA is a fascinating subject, and progressive research is being continuously carried out in this field.