The Scientific Testimony website reports DNA to be a material grown inside the bodies of living organisms. In an Australian court case where DNA-tested samples were used as evidence, a jury was told the chances of matching DNA evidence to anyone other than the suspect were 1 in 43 trillion, according to the Genetics website.
DNA is a long string-like substance described by the Scientific Testimony website as the building blocks of life. When DNA is tested, it is split into four bands known as A,T,G and C. A person's DNA provides the basis of every aspect of that person's genetic makeup, giving information on areas of the human body such as hair and eye color. DNA is described by the Australian Genetics website as important for a number of research purposes, including tracing genetic ancestry of living organisms.
By tracing the DNA of a person, testing can be used to provide a risk assessment of that person's chances of being affected by certain medical conditions. The National Cancer Institute reports that by studying the DNA of people affected by certain types of cancers, certain genes have been identified as being present in their bodies. By identifying these genes, DNA testing can be used as a preventative measure, allowing people at high risk to maintain high levels of preventative medical care in an attempt to lower their risk of becoming affected by cancers such as colon and breast cancer.
Colorado State University explains that the development of DNA testing for the purposes of identification was as important a breakthrough in the 1980s as the development of fingerprinting technology in the 1880s. DNA identifications testing is often used for the purpose of identifying the victims of crimes and terrorist attacks such as those on Sept. 11, 2001. The Genetics website reports DNA testing is often used for the purpose of eliminating a suspect from a police inquiry and, in other cases, for placing a suspect at the scene of a crime.
One of the most common uses of DNA testing is to provide information on the parentage of a child. The DNA Junction website reports that DNA testing is used for the purpose of testing the parentage of children in adoption, child support and custody, as well as for immigration purposes. As DNA is made up of a mixture of the DNA of a person's parents, the genetic structure allows the parentage of a child to be estimated to a 99.9 percent probability.
One of the purposes of DNA testing that has become controversial in the first decade of the 21st century is the storage of DNA samples in law enforcement databases. When crimes are committed the Genetics website reports evidence samples are often compared to those held on government databases to look for matches with convicted felons. There are many ethical concerns associated with the storage of DNA samples, including those surrounding the privacy of individuals.