Understanding the issue: What is DNA Testing?

People thinking of doing a paternity DNA test or infidelity DNA test may still not always have a clear idea of the answer to the question ‘what is DNA testing?’ The general grasp people have of DNA is that DNA is much like a finger print in that is unique, even more unique than a fingerprint. DNA is found in cells. Perhaps, there isn’t that much more each one of us needs to know, but a bit a deeper understanding would help.

Tell me More about DNA

DNA is an acronym for deoxyribonucleic acid.  It is found in every cell in your body although it is not found in red blood cells. DNA is found in long strands, in fact two long parallel strands. The DNA structure is commonly known as a double helix. These two strands are intertwined and would look, if seen under a powerful microscope, much like a spiral staircase.  DNA holds the information our body needs to survive. Anything from our physical characteristics, hereditary conditions, etc.  All our genetic information is encoded in our DNA. Our DNA is found in cell organelles called a nucleus and it is neatly arranged into a chromosome. During fertilization, we inherit 23 chromosomes from our father and 23 from our mother. These chromosomes pair up together so that we always have 46 chromosomes in our cell nucleus.

DNA is Unique

The fact that our DNA is unique makes DNA testing highly accurate. Two people can have an identical fingerprint although it almost impossible for them to share all ten. DNA can however, tell us vast amounts of information. A DNA Relationship Test can establish relationships between individuals, an ancestry DNA test can tell you your origins and your distant ancestry, a genetic predisposition test can tell you which autoimmune diseases you may develop over the course of your life; this list goes on and on.

What is a DNA test?

The terms ‘testing’ and ‘analysis’ are closely related but not exactly the same; however, the fact that the two are interlinked and very much part of each other means that any differences can be overlooked. When you send in your DNA sample, for example you might send a mouth swab containing cheek cells, laboratories need to extract DNA from your sample. There are three basic steps to get to the DNA; first, the cell must be ruptured. Secondly, the cell nucleus (structure within the cell containing the DNA) must be burst to free the DNA and the DNA protected from any enzymes that automatically attack it and begin digesting it. Once the DNA is isolated, then it is precipitated in alcohol.

The Two main Ways in which your DNA can be Tested

The following are the two main procedures for analyzing your DNA and are used in anything from paternity DNA tests to relationship tests and criminal forensic tests. The first type is Polymerase chain reaction, often abbreviated to PCR. This type of DNA testing procedure involves using an enzyme DNA polymerase. These enzymes are able to read the DNA code and make several replica of it with which scientists can work. Many times the quantities of DNA extracted are too small (for example in criminal investigations) and scientists would need to make copies to be able to work with.

The second type of procedure is called STR analysis. STR is an acronym for short tandem repeat testing. This test works by examining very specific areas or repeats on the DNA molecule. These repeats are amplified and the number of repeats analyzed. The difference between repeats in individuals creates the basis for genetic distinction between the two or more individuals involved in the test and thus, can show the absence or presence of a relationship. Our DNA is very similar from one person to the next, however, the minute parts of our DNA that are different forms the basis of this test and allows genetic analyst to create a DNA profile for any individual.

Thinking of doing a DNA test requires understanding the answer to question what is DNA testing. Essentially, clients are interested in the results rather that the intricacies of PCR and STR. However, understanding the general ideas conveyed above can give you a better grasp of your results.