When a child is born to a married couple, it is assumed that the husband is the biological father, and paternity is legally established. If there is any question about the paternity, a DNA test can be ordered. But with unmarried couples, paternity has to be established, which may include a DNA test for paternity.
Courts take these tests very seriously, relying on the results to make decisions. But how reliable are they? And could they be wrong?
Paternity Testing
A child’s DNA is the combination of 50% each from the mother’s and the father’s, DNA. In order to establish paternity and define who the biological father is, a “cheek swab” of buccal cells in the mouth of both the alleged father and baby.
DNA testing can also be obtained from a pregnant woman’s blood sample as early as 8 weeks into her pregnancy. Non-invasive, the testing takes advantage of the fetal DNA in the mother’s bloodstream, with higher concentrations available as the pregnancy progresses.
The DNA is compared to a sample from the alleged father (or fathers) to examine the similarities and establish the child’s biological father. But the results may not always be enough.
How Paternity Test Results Can Be Incorrect
While modern DNA testing accuracy can be as high as 99.999%, that tiny fault percentage can be from a number of factors.
· Incorrect collection or handling samples can affect and delay your results, especially if you’re requested to recollect a sample. Eating or drinking less than an hour before a cheek swab can also affect the outcome. Food or drink won’t change the DNA but can mask them. Don’t eat or drink for at least an hour before doing a cheek swab, and of course, carefully read any directions enclosed.
· Cross-contamination—don’t handle the tip of the wand that’s used for swabbing, and put one swab in one envelope only. And don’t re-use the packaging, use the envelope specified for swabs, one swab per envelope.
· Medical procedures, such as a blood transfusion or a bone marrow transplant, can alter the outcome because different DNA has been introduced into the body. This genetic material can hang around for a long time. Unless the blood or bone marrow was from a close relative of the alleged father, the results may be inconclusive.
· Tampered testing. Should a mother or another party have access to the sampling, it’s possible that the individual could tamper with the sample to change the outcome. While rare, it has been known to happen.
· Errors at the lab level, also rare, can happen, giving either a false positive or a false negative. Lab samples can be mislabeled, contaminated, or tested and handled incorrectly. If you suspect tapering or a lab error, you may want to order re-testing may, possibly with another lab.
· Related alleged fathers can produce a positive result. If the mother names an individual but has only had a relationship with a brother or other close relative, it’s possible that the wrong individual can be named the father.
· DNA mutations can also cause rare issues in testing. Mutations occur regularly, but if a man’s sperm contained a mutated strand of DNA, it’s possible that the child’s test may come back different. This is particularly true of older men who father children since DNA mutations can increase with age. Should the sample show two or more mutations, that would cause a red flag in the sampling.
· A “Chimera” is a very rare individual that has DNA from two separate individuals, meaning they have two sets of genes, similar to those who have had a transfusion or bone marrow transplant. They can occur when four parent cells—two fertilized eggs or two very early embryos—fuse together. In vitro fertilization can increase the chance of chimerism. Standard DNA testing may show that the actual father isn’t related to the child, even though he is actually the father.
How Accurate Was The Testing?
Older methods of DNA testing may not be as accurate, so it’s possible that doing an updated DNA test may be in order if you’re not sure. The State of Texas recently ordered re-testing in thousands of criminal cases that can change the outcome for incorrectly identified suspects who were arrested, charged and convicted based on less-than-accurate evidence.
A Compassionate Attorney For Your Family Law Needs
Wendy L. Hart is an experienced family law attorney helping people throughout Tarrant County who need help in a divorce. As a divorcee herself, Wendy understands the process as well as the difficulties involved. We represent both for men and women. We’ll make sure you’re treated fairly and will protect your interests and your children.
Visit our Mansfield office, use our online contact form, or call us at (817) 842-2336. We’re ready to help.