The only way to guarantee a child’s father’s identity is by performing a DNA test to prove paternity. Paternity tests are highly accurate and take either blood or tissue samples from the father and child before matching them. If the DNA samples line up, then the father and child are related. If not, then the child has another parent who is not yet known. You have a right to seek a paternity test if you question paternity at all.
Paternity tests are between 90 and 99 percent accurate. They can easily identify who is not a biological father of a child as well as show the likelihood of paternity for another. If you are involved in a contested paternity case, you will be asked to provide a sample to the court for testing.
Blood and tissue tests are available. Blood tests determine the biological possibility of being a child’s father but cannot identify paternity for certain. They look at blood types to determine if the child shares common markers with his or her mother and father.
DNA tests are much more accurate and preferred in most cases. These tests actually match the child and father’s sample tissues. Two or more DNA probes may be taken. The DNA should match on these tests. The tests compare the mothers, fathers and children to each other to see where the child’s characteristics are found in the genomes.
If the alleged father matches the child’s DNA on each probe, there is a 99.9 percent probability that he is the father of the child. The test requires only a simple cheek swab to collect tissue from the mouth, so it can be done very early in a child’s life.
Source: FindLaw, “Paternity Tests: Blood Tests and DNA,” accessed Aug. 03, 2017