The Role of Dna Technology in Crime Investigation

DNA forensics is a division of forensic science that focuses on the use of genetic material in criminal investigation to answer questions pertaining to legal situations, including criminal and civil cases. Through DNA testing, law enforcement officers are able to identify human remains or the individual responsible for a crime. DNA testing is a highly advanced scientific process that involves replicating the human DNA sequence to create a genetic map of an individual. Because of its reliability, DNA testing has become a significant factor in criminal cases. However, it has also been identified as having the potential to violate privacy and constitutional rights. The DNA identification process consists of five stages. These five stages

Human DNA is very similar to one another, but only about 0.1% is different from the next person. That 0.1% can tell a person’s eye color, hair color, and other physical features. DNA analyst are able to take a drop of blood, the size of a dime, and duplicate the number DNA found in that drop. With the ability to duplicate DNA, analysts can have a back-up, in the event a human error were to occur. Analyst can tell you exactly where your ancestors came from and the percentage that is still inside your DNA. DNA is a very powerful tool that can identify a murder if the individual left any blood, saliva, skin tissue, hair or semen. The education needed to be able make use of the DNA consists of a great deal of science classes.

From cases such as OJ Simpson to Chandra Levy, DNA profiling also called DNA fingerprinting or DNA typing has played a major role in the criminal justice system. The law enforcement community uses DNA profiling to rule out or identify suspects. Unlike hair microscopy, bite mark comparisons, shoe print comparisons, and firearm tool mark analysis, DNA typing has been developed through massive scientific research and has undergone meticulous scientific evaluation (Innocence Project). DNA is a foolproof method of identifying a perpetrator of a crime.

(PCR), which isolates small fragments of DNA that have a high degree of variability from

DNA is the genetic material that makes up the characteristics of all living organisms. While all human DNA is very similar in nature, there is just enough differences in

Due to the uniqueness of DNA it has become a powerful tool in criminal investigations

DNA forensics can also narrow down suspect pools, exonerate innocent suspects, and link crimes together if the same DNA is found at both scenes. However, without existing suspects, a DNA profile cannot direct an investigation because current knowledge of genotype-phenotype relation is too vague for DNA phenotyping. For example, a profile from a first time offender that has no match in any database may give the information that the criminal is a left handed male of medium stature with red hair and freckles. It would be impossible to interview every man who fits that description. However, with available suspects, DNA forensics has many advantages over other forms of evidence. One is the longevity of DNA. Although it will deteriorate if exposed to sunlight, it can remain intact for centuries under proper conditions (Sachs, 2004). Because DNA is so durable, investigators can reopen old cases to reexamine evidence.

Even though DNA evidence is generally linked to an offenders profile through DNA database. In the late 1980’s the federal government laid a ground work for the system of state, local and national DNA databases for the storage and exchange of the DNA profiles. This system was named the Combined DNA Index System (CODIS). Maintaining DNA profiles set of databases that can be shared to the law enforcements all across the country. The CODIS can compare crime scene evidence that has been stored to a database of DNA profiles obtaining previous offenders. This

When analyzing DNA, the analysts create a DNA profile for each evidentiary piece of DNA. The DNA profile is based on 13 markers, or locations, within the genome. These 13 markers are chosen because they show a high variability between individuals. By using these 13 markers, the probability of 2 individuals having the exact same 13 markers is infinitesimal. But DNA profiles as they are now are made for identification purposes only. The profiles are not meant to contain personal genetic information (Matheson, 2016). But through the work of Susan Walsh, together with colleagues in the Netherlands, they have been able to create models for eye colour and hair colour. For the model on eye colour, they have a 95% accurate predictability rate, but only for brown and blue eyes. They have not done as extensive of work on the other colours of eyes. For the model on hair colour, they have a 90%

to identify individuals through sampling a drop of their liquid body substance. DNA profiling, already

Every day DNA technology becomes more advanced and innovative, for example can match the smallest amounts of biological evidence to a criminal offender. Future DNA techniques will be applied to existing systems and testing methods that will become more automated and will be more effective and less time consuming. Instead of waiting months of DNA results the future will provide instantaneous means for DNA profile development.

Deoxyribonucleic acid profiling also commonly known as DNA is a biotechnological science, a forensic technique used to identify individuals by using their genetic sequencing, although most people have the same DNA they have different regions within their sequencing that makes them individual. Profiling is not only used for fingerprinting it is used to analyse saliva, skin tissue, blood, hair and semen. The procedure of DNA profiling is used to identify criminals, disaster victims and one’s pedigrees through paternity tests.

DNA Fingerprinting, also known as DNA Profiling, is a method used to identify a person using DNA patterns that are specific to him/her. 99.9% of DNA is identical in every human being, but .01% is enough to distinguish between people. It is most commonly used in criminal cases to link a criminal to his/her crime scene, but is also used for paternity/maternity tests, and immigration records. Usually a skin, hair, or body fluid sample is collected from a crime scene or criminal or test candidate, then DNA is extracted and cut using enzymes that recognize patterns in DNA and run through a gel by an electric current in a process called electrophoresis (Annely).

Law Enforcement keep notes on arrests that have founded people innocent of crimes, and retention of an innocent person's DNA can be charge or otherwise, seen as a invasion of that person’s privacy and civil liberties. Dr. Alec Jeffrey, a former professor at the University of Leicester laboratory, consulted with his lawyers to develop the new type of technique called DNA profiling. His technique would prove that DNA fingerprinting (profiling) can individualize evidence compared to the blood typing. DNA profiling compares 13 standard STRs to form a profile. The analysis used by the scientists, uses PCR and STRs to profile an individual. It is highly unlike that two individuals’ identical numbers of repeats for all 13 STRs, will match, which DNA fails is hardly never due to a successful match of 385 million to 1. This makes DNA profiling the most accurate tool in Forensics.

DNA fingerprinting is a technique that is used to determine how likely it is whether genetic material came from a specific person or family group. Since 99% of human DNA is identical, that means that it is only 1% of our DNA which is different, and it is that 1% that we look at when we are attempting to determine the origin of a DNA sample.