Legal vs. Home DNA Paternity Test

Home DNA Paternity Test
Advances in DNA testing technology have now enabled paternity DNA tests to be carried out on samples of saliva, and for the consumer this has meant that DNA paternity tests can now be carried out in the comfort of one's own home. In fact, whereas until recently, in order to perform a DNA paternity test, one had to visit a laboratory or a clinic, and have a blood sample taken, nowadays it is possible to carry out a paternity test using oral swabs that need to be simply rubbed along the inside of the mouth and the cheek. The samples are then left to dry and mailed back to the laboratory for analysis.
This kind of test is called a home paternity DNA test, and is very useful when one needs to have quick, reliable answers to paternity issues to satisfy one's own need to know. If, however one needs to use these results for legal matters, such as legal recognition of a child as being one's own, petitioning for child support and matters relating to immigration, one needs to order what is called a legal paternity test.
Legal DNA Paternity Test
In essence, a legal paternity test is a test in which the DNA samples are collected by an independent third party who becomes responsible for confirming the identities of the persons who are taking part in the test and assumes general responsibility for assuring that the DNA samples are not in any way tampered with. Therefore whilst in a home paternity DNA test, samples are usually collected by the participants themselves in their own home environment, a legal DNA paternity test usually necessitates a visit to a clinic or laboratory where the specialist will collect the samples.
Chain of Custody
This procedure is called maintaining the ‘chain of custody', and is necessary in order to ensure that the test results are reliable, valid and that this fact can be witnessed by an independent third party. For this reason, results of a home DNA paternity test cannot be used in a court of law, because there is no way of proving without doubt that the persons participating in the test on paper are indeed the same persons who have provided the DNA samples. So, for example, a person who does not wish to provide child support may send a sample from another person instead of his own, using a home DNA paternity test. For this reason, the results of a home DNA paternity test can be used for ‘informational' purposes only.
How the DNA test works
It is important to note that technically speaking, a home paternity DNA test is identical to a legal paternity DNA test, and that the difference between the two tests lies exclusively in the method of collection of the samples. In both cases the DNA of the child is compared to that of the father, to check for correspondence in the genetic markers. If a large number of genetic markers are found to be in common, the alleged father is confirmed as being the genetic father of the child. Modern DNA paternity tests are extremely accurate and reliable, and can confirm paternity with levels of probability greater that 99.99%.