What is Forensics DNA Technology?
DNA is the genetic material present inside the cells of the human body and almost every other living organism. Deoxyribonucleic acid or DNA is one of the most extensively studied topics of biology. In the healthcare system, DNA is one of the pillars of the whole biological structure. Now, what is DNA, what are its functions, and applications? These are some of the most common questions coming into our minds. In this article, we will discover more about DNA and all the questions related to it.
What is DNA?
DNA is called ‘Deoxyribonucleic acid’, and in its highly coiled form, is called a ‘chromosome.’ Under the microscope, it appears as an inter-coiled double-helical structure. The structure of the DNA and its composition can be understood in the following three points -
1. The two individual strands, also called the nucleotides, are ribose sugar strands that run antiparallel to each other. On these strands, nitrogenous base pairs are attached making genetic sequences, also called codons.
2. The nitrogen base pairs are categorized as purines and pyrimidines. Adenine (A) and Guanine (G) are the purines and Thymine (T), and Cytosine (C) are pyrimidines. A purine on one strand of the DNA is always attached to the pyrimidine on the opposite strand.
3. The purines are pyrimidines attached to each other with phosphodiester bonds, which hold the two individual strands of the DNA together.
4. DNA uncoils itself during the cell division phase, to make additional copies of the DNA.
What are the functions of DNA?
DNA is the carrier of genetic information from an individual into his/her child and is a very important medium for the identification of an individual by carrying out DNA fingerprinting. DNA fingerprinting or DNA Profiling is the process of studying the DNA in a laboratory to identify the markers. These markers serve as the basis of match-criteria among two individuals. The other functions of DNA include protein-synthesis.
What are the applications and uses of a DNA test?
Relationship DNA test - The main usage of DNA tests is in relationship identification. This type of DNA test is called a relationship DNA test, and includes the following:
Paternity DNA test - Paternity DNA is used for the identification of the biological relationship of an individual (usually a child) with his/her alleged father.
Maternity DNA test - Maternity DNA tests are used for finding out the biological relationship of an individual with his/her mother.
Siblingship DNA Test - For finding out, if a person is genetically related to his/her siblings or not?
Grandparentage DNA test - Grandparentage DNA test is used for finding out the genetic relationship of the grandchildren with their grandparents.
Prenatal Paternity DNA test - Prenatal paternity is required when the child is not yet born, but there is a doubt about who the biological father is? No sex-determination is done in the prenatal DNA tests, as doing so is a punishable offense and is inhumane, as well.
Immigration DNA test - A person who is applying for the Visa to a certain country may have to present proof of the genetic (biological) relationship between the sponsor and him/her.
Organ Transplant DNA test - It is the responsibility of the hospital, as well as the surgeon to get the DNA test done between the donor and the recipient of the organ, before the transplant is carried out.
Forensic DNA test - DNA tests done for criminal investigation are also one of the most popular types of DNA tests.
IVF and Surrogacy Baby DNA tests - These DNA tests are done for the identification of the real (biological) child born at IVF and surrogacy centers.
Ancestry DNA tests - Ancestry DNA tests are done to learn about one’s forefathers. These tests may include the regular ancestry, paternal lineage, maternal lineage, and GPS Origins DNA test.
NIPT or non-invasive prenatal trisomy tests are done to find the possibility of genetic diseases in unborn children.
Legal DNA test - Unlike the regular, peace of mind DNA tests, legal DNA tests are done on the court order and are always done under a proper chain of custody.
Other than these tests, DNA tests are also done for cell-line authentication which may be a part of some research or study based works.
What is a Forensic DNA test and how is it different?
A forensic DNA test is used by the law enforcement system to identify the suspects who are involved in criminal activities. In fact, the first DNA test was a Forensic DNA test. It was done in 1986 for identification of rape and murder case, by Dr. Alec Jeffreys. This case was the first time a DNA test was practically used for a purpose. Now after more than 30 years, there are hundreds of thousands of laboratories and private DNA testing companies doing DNA tests frequently.
Usually the biological samples left by the criminals at the crime sites, serve as a sample for a DNA test, which will later be presented as evidence of involvement of the suspect in the crime. Hair, semen, blood, skin, etc are some of the most easily available biological samples for a forensic DNA test.
Some countries have a complete online database of all its citizens’ DNA profiles, which are easily matched by the DNA samples received at the site of the crime. India, has passed DNA Technologies Regulation bill in 2019, which paved the way for India to create a similar DNA database, which would help the law enforcement agencies, to quickly identify criminals, based on a forensic DNA test report.
It is very important to choose the right testing laboratory or company for a reliable DNA test. Any company which is accredited by the National Accreditation Board for Testing Laboratories and Calibration or NABL, are deemed a standard lab/company for accredited DNA testing services. Another critical factor that should be considered in mind is that the company or lab must have the accreditations of related authorities if you are looking for an Immigration DNA test. Last, but certainly, not least, the DNA testing company or laboratory must have a good track record and a name for trust, reliability, ethical and fair practices, and timely report delivery.
