DNA is present in nearly every cell of our bodies, and we leave cells behind everywhere we go without even realizing it. Flakes of skin, drops of blood, hair, and saliva all contain DNA that can be used to identify us. As technology advances, forensic scientists are able to analyze smaller and smaller biological samples to develop a DNA profile. For example, if a person touched an object or weapon, skin cells may have been left behind. This low-level DNA is sometimes referred to as “touch DNA”. It can even be collected from a victim’s skin or bruises where they were handled roughly. Low-level DNA samples may be helpful when examining evidence where it would be difficult to retrieve fingerprints—such as textured surfaces on gun handles or automobile dashboards. This training will explain how crime scene evidence is collected and processed to obtain DNA and the laboratory needs to compare the victim’s or suspect’s DNA profile to the recovered crime-scene DNA.
The first part will allow the participants to use PCR to amplify the extracted DNA from different samples and compare it to a sample obtained from a hypothetical crime. Variable number tandem repeats (VNTRs) are regions in a genome that contain short stretches of DNA repeated a number of times. The number of repeats in a particular VNTR can vary from individual to individual. In this way, genetic variation in VNTRs can be used as markers for personal identification. The second part will focus on Short tandem repeats (STRs) which provide an excellent tool for this purpose because of their high degree of polymorphism and relatively short length. What are my career opportunities? This is especially beneficial only for students and professionals who have a passion for serious investigations and research projects in the role of DNA technology in forensic science.