DNA analysis has become crucial to criminal prosecutions in the last twenty years.
In some cases solving crimes from decades previously by retrospective analysis.
It is hugely important for detectives especially as by simply the smallest amount of DNA being found, can configure who exactly was at the scene.
It is also very important in the scientific arena as it can determine relationships between people and establish if they are in fact related to one another.
The key to the enormous impact DNA provides as evidence is that it is unique to a single person.
Indeed DNA holds the key to each person's uniqueness.
DNA is like a large database containing codes.
The codes are actually called amino acids.
They form the building blocks for proteins.
The codes themselves are uniquely sequenced within the DNA strands.
A particular sequence of codes can tell the body to make a protein that gives someone a particular hair colour.
In the forensic stage of prosecution the sampling of DNA can be difficult to get enough of a sample without contamination.
In cases of mild contamination the sample will have to be filtered through a system that removes the contamination but that doesn't damage the sample.
The sample is systematically broken up into different strands.
It is then passed through a system that can separately identify each code and hence the sequence, by separating each code and discovering its weight.
Improving technology means the entire process can take just a couple of hours instead of days, but not minutes or seconds as television shows would have us believe.