There are a number of ways through which doubts about a child’s parentage can be settled. The most common of these is the DNA test or a more out-dated, almost totally disused way, is by using a blood type chart or blood- typing, as it is commonly referred to. A man can opt for any one of these two tests although the most accurate results can only be provided with a DNA test.
When determining paternity by DNA, samples of the child’s DNA are taken, in order to derive a profile; usually samples are collected using oral swabs. The samples must then be sent to the lab for testing – obviously both the father and the child need to provide samples. The two samples are compared to see if the alleged father and child share the same genetic markers. In the event that the man is the biological father of the child, the test will usually give a 99.9% probability. This is because DNA is the material that is inherited by children from their parents. If the alleged father is not the real father, there will not be enough shared genetic material.
On the other hand, determining paternity by blood type chart is not really a test per se, it is more theoretical than practical in its approach to establishing parentage. Simply put, it is a chart that gives details of the expected blood group of a child’s blood, in relation to the blood type of his or her parents. Blood types are also inherited from parents and this is the principle under which a blood type chart works. For example, parents with an O blood group can only have children with an O blood group too (either O negative or O positive). A blood type chart provides information on the expected blood types of children from that of their parents.
Perhaps the greatest difference between these two paternity tests is that the blood type chart cannot be used as conclusive proof of fatherhood. It can only be used to disprove parentage and not to prove that an individual is the father of the child.
The DNA result is on the other hand very reliable. Unless there was a mistake in the testing process, the result is conclusive evidence of either parentage or non- parentage.
Another difference between determining paternity by DNA and determining paternity by blood type chart is the fact that for the blood type chart to be used, information on the blood groups of either one or both of the supposed parents must be available. In the absence of this information, the chart becomes obsolete.
There is also the obvious difference that the DNA test is actually a test that is carried out. An actual scientific test on the DNA profiles has to be done. When using a blood type chart in a bid to establish parentage, no tests need to be done. This is especially true when the blood group of each supposed parent is known. In such a case it is as simple as interpreting the information on the chart.