DNA testing is a process that is mostly used in forensics to identify individuals thorough their respective profiles. People can be identified through encrypted sets of numbers that reflect their genotypic fingerprint. Studies have shown that, although genetic information in humans is almost the same, there is enough genetic material that can distinguish one person from the other. However, monozygotic twins are an exception, and the process is not enough to distinguish them. ln order to identify a person, forensic experts use repetitive sequences, which are highly variable. These genetic sequences are called the VNTRs (Variable Number Tandem Repeats). Short Tandem Repeats or STRs are particularly preferred for this process. The loci of VNTR are very similar in people who are closely related. On the other hand, they are very variable in unrelated individuals, and it is highly unlikely for them to have similar VNTRs. This information can be used to test paternity, and other biological traits of a person. It is also used in criminal investigation especially in homicide cases.
History and Process of DNA Testing
The modern DNA testing method was invented in 1984 by Sir Alec Jeffreys while working at the University of Leicester in England. It was later introduced for commercial purposes in 1987 by Imperial Chemical Industries. The process involves collecting a sample of a persons genetic materials. The best method of doing this is carrying out a Buccal swab. A mouth swab reduces the risk of contamination. If this is not possible other methods can be used to collect a genetic sample from materials such as semen, saliva, blood or other body fluids or tissues. These samples can be obtained from personal items such as a razor, toothbrush or clothes. The samples can also be collected from stored materials like stored biopsy tissue or banked sperm. Additionally, blood relatives can provide samples that can be used for this process. This process should not be confused with genome sequencing, which is a process that entails complete sequencing of the genome of an organism.
You can find out more about the DNA testing process at StrictlyDNA.com.