DNA testing is a scientific process that can positively identify relationships between people from their DNA. Most commonly it is used to establish if a man is the true biological father of a child, however this is the same principle behind genetic genealogy, criminal tests or other relationship tests.

DNA (DeoxyriboNucleic Acid) is the body's genetic "blueprint". It is a long thread like molecule shaped like a twisted ladder that carries the genetic code which determines your personal characteristics, such as hair colour, eye colour etc. DNA is found in almost all cells that make up the human body, so a simple mouth swab can be used to take cells from the inside of your mouth for testing.

DNA testing allows scientists to look at different places on your genetic code which tends to differ between individuals. By examining DNA at a number of these variable regions scientists can determine how genetically similar two individuals are.

In the case of relationship or paternity tests, the success of such a DNA test relies on the fact that a child inherits half of the genetic material from each parent. As no two people in the world have exactly the same DNA except genetically identical twins, there is at least a 99.99% certainty of determining the biological relatedness of parents to a child or other family members.