Paternity Testing: Frequently Asked Questions
Why is accreditation important?
DNA relationship testing is not regulated by a government agency. Accreditation is the only safeguard a private individual has to know that a paternity testing laboratory is performing sound and accepted scientific methodology. (New York Residents: Accreditation is required by your state agency for all testing in New York).
PTC Laboratories is accredited by the American Association of Blood Banks, ANAB/ISO 17025 and the New York State Department of Health. PTC Laboratories also participates in proficiency tests multiple times per year with the College of American Pathologists and IQAS/Bode Cellmark Forensics. More information on Accreditations.
Why does mom need to be tested (since we already know she is the mother)?
Children receive half of their DNA from their mother and half of their DNA from their father. By comparing the mother's DNA and child's DNA we can tell which parts of the child's DNA came from the mother, because they match exactly. This lets us know that the remaining part of the child's DNA came from the biological father---so we know what to compare to the tested man. But without mom, we cannot eliminate part of the child's DNA. So even if the tested man is matching part of the child's DNA, we don't know if he is matching parts that came from the biological father, or from the mother. Without the mother, there is a greater chance that even if the DNA tested man is matching the child's DNA the matches could be random and the man might not really be the child's biological father.
In order to ensure the accuracy of a motherless DNA paternity test, it is often necessary to perform additional and/or more discrimination DNA testing. PTC Laboratories provides the same high guarantee on a motherless DNA paternity test as a paternity test that includes the mother. In order to obtain this high degree of reliability additional DNA testing may be necessary and the paternity test may take longer.
Can a paternity test be performed before the baby is born?
Yes. There are several ways to perform paternity testing before the child is born. See our prenatal page for a description of the different choices.
The mother's doctor can perform an amniocentesis or CVS procedure to extract a sample from the baby during pregnancy (usually after 12 weeks) or instead utilize a non-invasive method using the mother's blood to get the baby's sample. The sample is then sent to the laboratory to provide the child's DNA for paternity testing.
There can be significant cost to perform the amniocentesis. More importantly, the amniocentesis presents medical risks to the mother and the child. You should discuss those risks with your doctor. Because of those risks, most doctors prefer not to perform an amniocentesis unless there are medical reasons requiring the procedure. If the mother is going to have amniocentesis for medical reasons, then a paternity test can also easily be performed.
Another method that can be used is Chorionic Villus Sampling (CVS). This method of testing has increased risk (including birth defects), but can be performed a few weeks earlier than an amniocentesis. If CVS is going to be performed for medical reasons then it can also be used for paternity testing.
A non-invasive test can be performed as early as 9 weeks and requires a blood collection from the mother.
We live in different cities. Do we all have to be tested at the same place?
There is no need for everyone to be in the same city in order to be tested. We can have the specimens collected anywhere in the country (and most places in the world). For example, if the mother and child live in Atlanta they would go to a swab collection location there to have their specimens collected and if the alleged father lives in San Francisco then he would go to a swab collection location in San Francisco to have his specimen collected. All 3 specimens will be shipped to our DNA paternity testing laboratory overnight and the paternity test will begin once we receive all specimens.
We are not giving our specimens at the same time. How do I know the right person was tested?
In addition to checking photo identification an instant photograph is taken of everyone paternity tested. A right thumbprint is also taken on the DNA tested adults.
Occasionally an "imposter" will come in for a DNA paternity test. Most often when this occurs the alleged father sends a friend in to have his DNA specimen taken. When this happens the mother can look at the photograph and tell us that the man DNA tested was not the alleged father.
Often the alleged fathers worry that even though they can identify the mother, they may have never seen the baby or it may have been several years since they saw the child. They want to know how we can be sure we are testing the right child. In the case of an infant, it would not be possible for the mother to bring in someone else's baby because the test will show that it is not her child. In unusual cases it may be necessary to take extra precautions to ensure that the right child is tested. It may be necessary to have the child's DNA specimen taken in front of an attorney or doctor or other credible person who can verify the identity of the child.
Why does the test take so much longer than on TV?
There are two types of television shows that portray DNA testing and neither gives a very clear picture of what really happens.
The first type is talk shows, shows like Jerry Spinger and Montel Williams (both of which PTC Laboratories has performed DNA paternity testing for). In these shows, it often appears that participants are DNA tested and the paternity test results seem instantaneously available. In actually, these shows are often filmed several days after the DNA testing specimens were collected and the results are available prior to the filming of the show.
The second type is television drama, shows like CSI and Law and Order. These shows often portray the collection and results of DNA evidence that is not suitable for DNA testing as well as results in minutes from the time of submission to the laboratory. In reality, normal STR DNA testing can be completed in days under average circumstances and you need to ask about DNA sample types before you submit anything to a DNA paternity testing laboratory (Example: Cut hair is not a good sample).
Most people needing DNA testing do not have a DNA paternity testing laboratory close enough to them to have their samples collected at the site where the DNA paternity testing will actually take place. Therefore, the samples must be shipped by overnight courier to a DNA paternity testing laboratory who will begin DNA testing after they receive the samples. Sometimes this is the day after collection or can be even later if you are collected on a Friday or late in the day. Once the samples are received at the DNA paternity testing laboratory, DNA testing begins and results are usually available in approximately 3 working days.
Should we have a legal or a non-legal test?
What Makes a Paternity Test Admissible in Court?
A legal DNA paternity test should be performed if the paternity test report will be used for any legal purpose. This would include establishing paternity for Social Security, child support, inheritance, health insurance, or any other time that proof of paternity is necessary.
A non-legal DNA paternity test may be used when the information is only for personal informational purposes. There are a variety of circumstances when a non-legal paternity test is adequate. An adult child may wish to verify that the man who raised them is truly their biological father, or a legal father of a child may be less than certain that the child is truly his biological child, or any time that the test will not be used to establish identity or for a legal purpose. A non-legal DNA paternity test is for personal knowledge only. It is of no use for legal purposes.
To be admissible in court a DNA paternity test must meet two requirements.
First, the test must be performed by a DNA paternity testing laboratory that is accredited by the American Association of Blood Banks (AABB).
Second, the DNA specimens used in the DNA paternity test must have been collected, shipped and stored in a manner that establishes a good chain of custody for the specimens. This allows the DNA paternity testing laboratory to prove that the individuals whose names appear on the paternity test are truly the individuals who provided the DNA samples that were DNA paternity tested.
The chain of custody begins with the DNA specimen collector attaching a picture of the collected individuals to the form used to collect the DNA specimens (often referred to as a Specimen Collection Form or Chain of Custody Form). The DNA collector also checks a photo ID such as a driver’s license, and takes a thumbprint of the DNA tested individuals. Additional procedures may also be followed. The specimens must then be shipped to the paternity laboratory and stored at the laboratory in a manner that ensures the security of the specimens.
What Makes a Paternity Test Acceptable for Other Official Purposes?
Even if you do not want to use your DNA paternity test in court, you may need it for other official purposes. For example, you may need it in order to obtain Social Security benefits for the child, or to have the child placed on the father’s health insurance, or to change or add the father’s name on the child’s birth certificate. For various agencies to accept your DNA paternity test results, the DNA paternity test will usually need to meet the same requirements as if you were going to have the DNA paternity test admitted in court.
Why Obtain an Official Paternity Test rather than a Home Test?
Even if you do not intend to use your DNA paternity test in court, circumstances may change and you may want to use it in court at a later time. Also, you may eventually need an official paternity report for such things as health insurance or Social Security benefits. Whenever possible, it is much better to have the specimens collected in a way that allows the test to be used as an official document if necessary. In that way you avoid having to pay for another DNA paternity test whenever the need for an official DNA paternity test arises.
Is the test confidential? Who can get the results?
The DNA paternity test is completely confidential. The mother of the child and all adults DNA paternity tested are entitled to receive the results of the DNA paternity test, as well as copies of the pictures of everyone who was DNA paternity tested. The only other people who can get results of the DNA paternity test are those designated by the DNA tested adults or a legal guardian of a DNA tested minor child. For example, the mother and alleged father may want DNA paternity results sent to their attorneys.
No one else can get any information about the DNA test. They can not even find out whether an individual was DNA paternity tested, unless we have permission from a DNA tested individual to give out that information. However, if PTC Laboratories receives a subpoena or court order to produce documents, we are obligated to comply.
The mother and alleged father are not able to receive personal information about each other. For example, PTC Laboratories will not give the mother information such as the alleged father's social security number or address.
Can the test give the wrong result?
Yes, the DNA test can give the wrong result. PTC Laboratories takes many extra precautions to prevent this from happening. As far as we know, we have never given out a wrong result.
If the child and the DNA tested man do not match at three or more tested DNA locations, then the tested man can not be the biological father of the child. If all of the parties samples were not collected at the same time, requesting to see the photographs of the other parties may be prudent to ensure the correct people were DNA paternity tested.
On the other hand, when the alleged father and child have matching DNA, the alleged father is not the only one who could be the biological father of the child. The test only determines how likely or "probable" it is. The higher the probability of paternity or paternity index, the more certain it is that the DNA tested man is in fact the child's biological father.. Click here to see more information on Avoiding Erroneous Results.
Why does a higher probability of paternity matter?
AABB accredited laboratories are only required to DNA paternity test to a 99% probability of paternity. A DNA paternity test at a 99% probability of paternity has identified a DNA genetic pattern that, on average, 1 out of every 100 men would have. Thus many people have this same pattern and would show the same result on the DNA paternity test. At this level of reliability a DNA paternity test would give the wrong result (a "false positive") for 1 out of every 100 non-fathers who are DNA tested.
PTC Laboratories guarantees a minimum probability of paternity of 99.99% on every DNA paternity test (motherless and mutations included). At a 99.99% probability of paternity, on average the identified DNA genetic pattern will fit no more than 1 in every 10,000 men. Most of our DNA paternity tests are even more discriminating than that. Avoiding Erroneous Results or How to choose a Paternity Laboratory.
Do I need to test both alleged fathers if they are brothers?
Yes. If there is more than one possible father of the child and the possible fathers are closely related to each other, then it is very important to DNA test them both. This would be true, for example, if two potential fathers are related to each other as brothers or as father and son. The DNA paternity test of a single alleged father only identifies a probability of paternity for that alleged father compared to other unrelated men. If two possible fathers are closely related, then their DNA genetic makeup can be very similar, and they could easily both receive a positive DNA paternity test result (alleged father's that are identical twins will either both match the child or both be excluded). Except for identical twins, the laboratory will continue testing until one of the alleged fathers is excluded (at no extra charge). If only one of the related alleged fathers is available, the client can pay the laboratory to perform additional DNA paternity testing in order to establish a likelihood that the DNA tested man is the biological father as opposed to the unavailable relative. But it is best to DNA test all related parties who could be the father of the child.
Is taking a paternity test a good idea?
There are a wide variety of reasons to have DNA paternity testing done. Many DNA tests are performed on newborns. Sometimes there is more than one candidate for fatherhood. Sometimes the mother knows who the father is, but the father wants to be sure. In other cases the parties may know who the father is, but need to have official proof. This can happen if the parties were not married at or near the time of the child's birth. Official proof may be required for many reasons including health insurance, Social Security benefits, child support, child custody, visitation, adoption, immigration or inheritance.
A DNA paternity test is not always a good idea. You should consider all of the possible consequences before deciding to take the DNA paternity test.
For example, it sometimes happens in the heat of an argument that a mother will tell a presumed father for the first time that he is not really the child's father. Some men pursue a DNA paternity test to find out. But if the man loves the child, has a good relationship with the child, and intends to continue to love and support the child even if proved not to be the biological father, then a DNA paternity test is probably a bad idea.
Some men rationalize that they just need to know. They say it will not affect their relationship with the child, and they won't ever tell the mother they took the test, no matter how the test comes out. Most often this is simply unrealistic.
If the DNA paternity test indicates that the man is not the child's biological father, then it may subconsciously and unintentionally change his attitude and behavior toward the child. The DNA paternity test results sometimes also slip out unintentionally in a heated argument with the mother, or the mother may find the laboratory report, or may hear about it from someone the man has told. This may even cause the mother to prevent a continuing relationship between the man and the child.
It is also possible that the child may somehow find out about the test. Learning that the man is not the child's biological father may have a serious impact on the child's self-image, and the child's assumptions about how the man feels toward the child. This can occur even if the man assures the child that his feelings toward the child are unchanged. There are many other possible adverse consequences of the paternity test in this situation. They depend, in part, on the individual facts of each case.
Please carefully consider all of the possible consequences before deciding to take a DNA paternity test. There are many possible reasons to take a DNA paternity test. But if you are a man who has assumed that you are the child's father, and you and the child have a good loving relationship that you want to continue, and if the only reason to take the paternity test is "because you have to know," then please carefully weigh the possible consequences before setting up a DNA paternity test. Please think of the child's needs, and make the choice that best protects and promotes the incredibly important relationship you have with your child.