Forensic DNA Analysis

If you have ever wondered if you were related to the Vikings or who your birth parents were or who committed a particular crime, then DNA may provide your answers. In respect to DNA analysis, blood sampling is only one aspect. There are as many ways in which distinct DNA characteristics can be harvested as there are reasons for the process.

Forensics is one of the more popular pursuits in which the general population can appreciate the analysis of DNA. Everyone wants to catch the bad guy, right?

Purpose of Forensic DNA Analysis

dnaThe study of forensics involves the analysis of a particular area of study for the purposes of criminal inquiry. Applying forensics to the DNA of an individual can reduce the question of doubt almost to zero if done correctly. If the DNA of a particular individual is harvested, it can be done in a variety of ways like blood, saliva, semen, vaginal lubrication and bodily tissues.

An investigation that hinges on sheer testimony alone can be completely overturned with the proof of a person’s DNA analysis. The DNA profile can oftentimes prove to be the clincher in a case due to the unique fingerprint like quality that the human body’s deoxyribonucleic acid provides. It only takes one tenth of one percent of human DNA to distinguish between one person and another.

History of Forensic DNA Analysis

During the nineteen-eighties in the United Kingdom, there was a particular murder case that involved two teenagers. Dawn Ashworth and Lynda Mann had been raped and murdered within the span of three years. The local Leicestershire Constable obtained blood samples from close to five thousand men, from which they compared the samples to the victims. There was only a conviction of guilt without question when Colin Pitchfork was sampled.

He originally evaded the police by having a friend stand in for him at the time of testing, only to be found out eventually. Once the police heard of his deception, they tested his blood and found that his presence could be confirmed at both crimes. This ultimately led to a full confession by Pitchfork and the first crime to be solved by DNA analysis.

Science Behind Forensic DNA Analysis

In addition to the gathering of blood, urine, tissue and bodily fluids, the reference sample needed to create a person’s DNA profile can be collected several other ways. Blood relatives can provide samples as well as sperm and tissue banks. There can even be samples obtained by analyzing human remains.

The reference sample is then purified by breaking the DNA away from the cell and its contents. There are several different ways to then analyze the DNA such as the Southern Blot method, Polymerase Chain Reaction analysis, mitochondrial analysis, y-chromosome analysis, amplified fragment length polymorphism (AmpFLP) and STR (Short Tandem Repeats) analysis. The bulk of what is used today around the world involves some form of STR analysis.

The amazing thing about our DNA is that the code in our cells is derived from the same two people. Half of our information is from our mother and half from our father. It can be harvested anywhere on our body from the day we are conceived until well beyond death. This makes DNA analysis one of the most marvelous tools for justice systems ever to be discovered. The human genome can be quite convincing and convicting.