If you’ve ever watched a crime drama on television, then you’ve probably heard the phrase “forensic testing” before. On TV, it’s what the scientist does that leads to finding suspects. It usually also means catching the criminal in the last 10 minutes of the show. While this process actually exists, it is not normally as fast or as easy as entertainment makes it out to be. What is a forensic test? Forensics testing is a process by which lab technicians examine deoxyribonucleic acid, or DNA, to determine the identity of a person attached to the sample for a number of different reasons. The most common is usually related to criminal activity and trying to determine whether a suspect committed a crime or did not. It is an excellent tool for determining a person’s identity when you absolutely need to know. There are several different ways to examine a DNA specimen to determine who it belongs to. Experts collect these DNA samples are from internal or external sources. For instance, blood or skill cells are very valuable genetic materials for forensic testing. But how is forensic testing done?
Forensic Testing Methods
The forensic DNA testing process is completed in several different ways and methods. While different scenarios call for different kinds of forensic DNA testing, the following are the most common that scientists and lab technicians could use.
- Short Tandem Repeat (STR) This method is the most-used for crime scene investigation and crime-related forensic testing types. It relies on a genetic sample about the size of a quarter to get results. It is useful for more most situations that require forensic testing, and the FBI has an established database for forensic labs that use this process to help create a baseline for the standard tested 13 specific STR loci. That’s because the likelihood that two people who aren’t identical twins will have the same exact 13 STR loci is approximately one in one billion.
- Restriction Fragment Length Polymorphism (RFLP) This method was used to build the earliest form of genetic fingerprinting. This can be used to identify suspects from genetic material left at a scene. RFLP is still useful for finding markers that point to genetic disorders or diseases. Scientists used RFLP to map the human genome.
- Polymerase Chain Reaction (PCR) This method of DNA replication copies small DNA samples. The process uses polymerase to replicate different strands of sample DNA to create more useable material for other testing methods. It is important for tests that require larger amounts of DNA or for increasing the usability of small samples. PCR helps build a DNA profile.
- Y-Chromosome Analysis Y Chromosomes are passed directly from father to son. Y chromosome analysis is perfect for determining paternity in males. This makes it valuable to situations involving inheritance, infidelity, or a simple test to determine parentage. It helps determine the number of men involved in specific crimes by identifying different y-chromosomes in genetic samples.
- Mitochondrial Analysis This forensic testing technique uses information from a different part of the cell than STR testing methods. It’s possible to gain DNA evidence from materials like bones and hair fragments with mitochondrial analysis. That means old evidence would still be useful for this updated testing technique.
Do Forensic Scientists go to the Crime Scene?
Watching crime dramas might lead you to believe that the people who do forensic testing services show up at different crime scenes in a pair of sunglasses with a witty retort. While it is possible for actual forensic scientists to go to the field if necessary, they spend most of their time in a lab running tests. Crime scene investigators spend a large part of their training learning the best evidence gathering techniques. This guarantees that forensic scientists get what they need to conduct forensic tests and get results.
Forensics and Crime
How are forensics used to solve crimes? We’ve identified some of the different types of forensic testing methods used by laboratories around the world. But that doesn’t answer how it’s possible to catch a criminal with these tests. Forensic science compares genetic markers from the suspect and a sample left at the crime scene. This helps exonerate or incriminate someone the police have in custody. It is also useful for determining who is related and if someone is who they claim to be when someone wants to claim an inheritance. It is even possible to identify a narcotic with forensic drug testing. The process is useful for identifying types of drugs, as well as the person or entity that produced it based on its chemical makeup. How long do forensic tests take? It depends on the type of testing the forensic scientists are running, versus how much genetic material they have at their disposal. Some tests take anywhere between 24 to 72 hours. But due diligence means that some tests might take even longer. If you’re in need of a lab for forensic testing in the Merrillville and Hammond, IN area, contact the genetic testing experts of Choice DNA at 800-219-4362 for lab results that are reliable and admissible in a court of law.