A paternity test is a medical procedure intended to establish the identity of a child's father, by cross-matching the DNA patterns of both parents with the child's. Paternity tests are recognized, almost irrefutably, by the legal system as a viable means of determining fatherhood, especially in cases where child support is requested. Some jurisdictions will not allow child support to be terminated once it is ordered, even against a subsequent test denying paternity. For this reason, accuracy and reliability in testing are essential.
How Test Are Done
Samples of DNA are collected from the the suspected father, and the mother, along with the child. These specimens are then looked at for similarities. Clinicians codify the DNA and examine data at certain points of interest, seeking common matches. Different test methods vary in the amount of locations targeted for information. There are two tests most commonly used to establish paternity: the Polymerase Chain Reaction, and the Restriction Fragment Length Polymorphism.
Polymerase Chain Reaction
A PCR test is the fastest of the two, only requiring between three and nine days for results. This method necessitates a very small amount of material for testing and, therefore, is often collected from a cotton swab to the inside of the cheek. The disadvantage of a PCR test is that it examines DNA at locations with less variable sizes. Because of this, less information is garnered from the process regarding paternity than with an RFLP.
Restriction Fragment Length Polymorphism
An RFLP requires a greater sample to be tested and, therefore, is commonly done by extracting a vial of blood. It is the more reliable of the two tests, though results take a bit longer to return. Although the RFLP can ascertain paternity at a significantly higher probability, either method executed correctly should bring forth accurate results. Any of the two tests can actually be performed well with a specimen from the mouth or blood.
Considerations
The American Association of Blood Banks is an organization dedicated to upholding the highest standards of professionalism in the transfusion industry. Currently, laboratories offering paternity testing are not obligated to obtain specific licensure, but an AABB accreditation certifies that a facility is testing in correspondence with the most reliable methods known at present.
Misconceptions
Many research facilities offer testing to an accuracy of 99.0 percent. While this appears to be a very high ratio, it is not. A 99.0 percent probability means that a genetic pattern has been determined that matches, roughly, one out of every 100 men in society. Tests that declare a 99.99 percent probability are 100 times more accurate.
