Forensic science is a key instrument for the detection or investigation of crime and the conduction of justice by providing crucial information about the evidence found at the crime scene. Forensic biotechnology is an area of medical science that experiences constant breakthrough every now and then.
Forensics, short for forensic science, is the application of science in a legal setting. Biotechnology is used by forensic scientists to collect or process trace evidence such as hair, skin, blood or semen samples, which is found at crime scenes. An important aspect of modern forensics is the use of DNA profiling, or genetic fingerprinting. Sources of DNA include blood, hair, semen, saliva, bone and tissue. Every person has a unique DNA profile. The only exception to this is monozygotic twins. The chemical structure of everyone’s DNA is the same. The only difference between people is the order of the base pairs.
Forensic analysis of biological evidence using biotechnology methods is increasingly important in criminal investigations. Analysis of proteins in blood (serology), other body fluids and body tissues are some of the traditional methods in forensic analysis.
DNA forensics is now revolutionizing many aspects of criminal investigation which include;
- DNA fingerprinting
- DNA foot-printing
- DNA profiling
- Polymerase chain reaction (PCR) analysis of DNA samples allows precise identifications to be made from very tiny bits of evidence collected at the crime scene
Using these sequences, every person could be identified solely by the sequence of their base pairs. However, because there are so many millions of base pairs, the task would be very time-consuming. Instead, scientists are able to use a shorter method, because of repeating patterns in DNA. To identify individuals, forensic scientists scan 13 DNA regions, or loci, that vary from person to person and use the data to create a DNA profile of that individual (called a DNA fingerprint). There is an extremely small chance that another person has the same DNA profile for a particular set of 13 regions. With the help of a technique that amplifies DNA, the PCR (Polymerase Chain Reaction), which is used to make millions of exact copies of DNA from a biological sample, it is possible to determine DNA fingerprinting even analyzing a very small quantity of DNA.
The technique of DNA fingerprinting is based on the analysis of two types of highly variable sequences present in the human genome: VNTR ( Variable Number Tandem Repeats) and STR (Short Tandem Repeats). By combining the information obtained from the analysis of more VNTR or STR regions it is possible to obtain the distinctive profile of a person.
Forensic biotechnology deals with the study and investigation of genomic information for the identification of specific signatures. The data obtained from forensic biotechnology are used by the legal system to make necessary interpretations about criminals. Because of its potential to identify unique genetic markers, the discipline has also been employed for the determination of parenthood or other familial characteristics.
Biotechnology is the root of any DNA Forensics (Identification) application. It helps in following:
- Identify potential suspects whose DNA may match evidence left at crime scene
- Identify exonerate persons wrongly accused of crimes
- Identify crime and catastrophe victims
- Establish paternity and other family relationships
- Identify endangered and protected species as an aid to wildlife officials (could be used for prosecuting poachers)
- Detect bacteria and other organisms that may pollute air, water, soil, and food
- Match organ donors with recipients in transplant programs
- Identification of pedigree for seed or livestock breeds
- Authenticate consumables such as caviar and wine
The following two techniques are commonly used in the area of forensic medicine mostly in resolving legal issues:
- DNA Fingerprinting using Mini-Satellite DNA
- The probes correspond to hyper- variable minisatellites in DNA
- Autoantibody Fingerprinting using Dipsticks