Paternity DNA testing determines the biological father of a child. DNA is a building block of life; it contains information for our tissues' and organs' development and their proper functioning. It has two copies, and we inherit one copy from each of our biological parents. By comparing a child's DNA with the parents' DNA, laboratories can determine biological relationships.
Participants and Accuracy
The tested parties in a paternity DNA test usually are the child, the presumed father and the mother. The mother's participation makes the testing easier and faster, but it is not necessary. Even though each child inherits DNA from his biological parents, the child's DNA is specific to that child, because some parts of DNA differ from parent to child. Careful DNA testing can exclude a man as a father, but it cannot prove that a man is definitely the father. Even so, DNA testing labs offer more than 99 percent accuracy in determining the biological father.
How It Works
One type of paternity DNA testing amplifies a specific piece of DNA in a reaction called PCR--polymerase chain reaction--and highlights it with fluorescent tags to show sections that will be compared between a child and a man. The other type, called RFLP--restriction fragment length polymorphism--uses specific enzymes to break the DNA sections apart. An electric field then segregates these DNA sections by size. Since the enzymes recognize specific sequences in DNA, the sections these enzymes produce are compared to identify the biological relationship.
Obtaining Samples
Postnatal--after the child's birth--DNA testing involves isolating DNA from the blood, a cheek swab, the umbilical cord or other samples. It poses no known risks to the participants. Prenatal--before the child's birth--testing is often discouraged because of the risks of harming the baby or of miscarriage. In these tests, the doctor uses ultrasound to guide a thin needle into the uterus and draws out a small amount of amniotic fluid or chorionic villi, fingerlike pieces of tissue attached to the wall of the uterus. These samples are then tested. Home DNA paternity tests are sufficient for personal knowledge and convenience but are not court-approved.
Importance
Establishing paternity is important for protection of a child's rights, including access to legal and social benefits, such as Social Security and veterans benefits, as well as inheritance. It can help provide an accurate medical history for the child and can also strengthen the bond between father and child.
Providers and Cost
The American Pregnancy Association advises those who seek paternity testing to use a testing facility accredited by the AABB, formerly the American Association of Blood Banks. Paternity testing from an accredited laboratory typically costs between $400 and $2,000, depending on the area where participants live and the type of testing chosen. Home DNA paternity testing is less costly.
