When you order a DNA paternity test, what do you expect it to tell you? DNA paternity testing has become so mainstream, and the technology is now so advanced, that some people may expect results to show not only the paternity results, but also specific details and characteristics about each participant. In truth, the reality of what you learn is somewhere in between. Here’s a quick primer on what a DNA paternity test can – and can’t – tell you.
What a DNA Paternity Test CAN Tell You
Whether or not a possible father is considered the biological father
This is the whole purpose of using DNA as a testing method for paternity, and it’s by far the most reliable and cost-effective way to determine whether or not a possible father is the biological father. Positive results typically give a probability of paternity of 99.99% (or higher!), and negative results are always 0%. There’s no room for doubt with results like these. When a child’s DNA is tested directly with the possible father’s DNA, a definitive determination one way or the other is almost always the outcome. If you need help analyzing results, our experts are there to help.
A participant’s sex
One of the things checked during a DNA paternity test is whether or not the participant is male or female. This is extremely helpful for a variety of reasons. For example, let’s say someone who orders a test is trying to determine the paternity of their son. When samples are tested, if a technician determines the DNA is from a female instead of a male, the lab can contact the person who ordered a test and ask for a clarification of who the sample belongs to or ask for a sample recollection, if needed. Sometimes DNA gets mislabeled by a client or even contaminated, and so determining a participant’s sex during the testing process is an essential step.
What a DNA Paternity Test CAN’T Tell You
If a possible father has sent in his buddy’s DNA instead of his own
When you use an AABB-accredited lab like DDC (parent company of HomeDNA Paternity), DNA paternity test results are guaranteed accurate, based on the samples the lab is given. So if a possible father swabs his friend’s cheek for DNA and sends it in under the possible father’s name, the lab assumes on good faith that it is really him and will give report results accordingly. To prevent this kind of fraud, participants (possible father, mother, child) can all collect DNA samples in the same room and send them in together or pay a little extra for a court-admissible legal paternity test, where all collections and submissions are supervised by an impartial third-party.
A participant’s age
Sometimes if there are two possible fathers and those fathers are biologically-related, people think a paternity test can determine which one is the father based on the ‘age’ of the ‘real father’s’ DNA. The truth is it’s not that simple. The only way to determine someone’s age based on their DNA would be to compare a sample taken at birth with a current sample (The Tech). And even that would be an educated guess.
Who the biological father is, if the two possible fathers are identical twins
Identical twins are unique in the population in that they have almost exactly the same DNA. There are 15 genetic markers used for a ‘regular’ test. In order to determine which identical twin is the father, the entire genome sequence for both men would have to be analyzed. This can add up to as many as six billion markers! This makes paternity testing practically impossible and definitely impractical (from a cost perspective) for most people.
If you are the grandparent (or aunt, uncle, brother, sister, cousin, etc.)
The HomeDNA Paternity home kit is designed for determining the relationship between a potential father and child, which is why the testing fee figures prominently on the box. A paternity test for this price must include the potential father’s samples. If you are trying to connect the dots and determine paternity without the father, you can still use the swabs in the kit to collect DNA from biological family members. Keep in mind, however, that you now are no longer doing a paternity test: you are doing “family reconstruction” testing. This involves testing family members with the child in question to determine a biological relationship and requires much more extensive analysis. For this reason, pricing starts at $399. To see what your options are, we highly recommend you contact us for more information about paternity testing without the father.
>> LEARN MORE ABOUT FAMILY RECONSTRUCTION TESTING
The Bottom Line
There’s nothing more accurate or cost-effective than a DNA test to determine paternity. It’s just essential to keep in mind that results for this type of test are very specific in their intent: They are designed to tell you whether or not a possible father has a biological relationship with the child in question. Period. If you have other questions that could be answered via DNA, such as whether you are the grandparent, then other types of testing might be the best choice for you.
Follow us on Facebook and Twitter! If you have questions about paternity tests or other DNA testing services, please contact our Client Support Center at 888-404-4363, Mon-Fri from 8:30 AM to 5:30 PM Eastern Time. Our friendly, expert representatives are ready and happy to help. Get answers anytime by visiting our Help Center.
Resources
“Understanding Genetics.” Understanding Genetics. The Tech Museum of Innovation, 29 Apr. 2004. Web. 02 Dec. 2015. <http://genetics.thetech.org/ask/ask8>.”What Is a Prenatal Paternity Test?” – Health Questions. Gov.UK, 28 July 2015. Web. 24 Nov. 2015. <http://www.nhs.uk/chq/Pages/what-is-a-prenatal-paternity-test.aspx?CategoryID=61&SubCategoryID=615>.
Evelyn Hardy says
Suppose a mother had two children and the father is claiming one but not the other. Can DNA testing of the two children determine if they have the same biological father?
Admin says
Hi, Evelyn. Is the father not willing to be tested? Because that would be ideal and the most cost-effective way to determine paternity of the children. If he’s not willing, we can do a full vs. half sibling test on the children and would also need the mother’s DNA. Cost for this type of testing starts at $399. To determine what type of family relationship test is best for your situation and/or to schedule a test, contact us directly at 888-404-4363.
Brandy says
I sent my test off an done it by hand An didn’t make a call in pin what do I do
Identigene says
No worries, Brandy. That pin is only needed if you intend to call us about your case.
Randall says
Can testing show if two presumed siblings had the same mother without her DNA?
Admin says
Hi, Randall! It depends on who else is available to participate in testing. Ideally, both fathers would participate, the alleged mother’s grandparents (if one or more are still living), or the alleged mother’s brother or sister. Because of the extensive analysis involved, this type of testing starts at $399. I suggest you contact one of our experts directly at 888-404-4363 (M-F, 9 AM to 5:30 PM Eastern), and they will be able to assess your situation and give you your best testing options for a conclusive result.
joanne white says
hi can me my grandsons mother and grandson be tested to determine if hes my blood grandchild as my son isnt around iv never doubted it but needs to be done i am the grandmother mother of the chids father but the chids mother wants to no hundred percent but obviously my son isnt around so i do it with the childs mother and child ????
Admin says
Hi, Joanne. You sure can! If the paternal grandfather is available too, that would be best, but we can definitely test with just you. It’s essential that the mother test too, in this case, along with the child. Because of the more extensive analysis required, the lab fee for this kind of test is $399 ($350 both both grandparents), and results are posted in 5 business days. If you have more questions, or to set the test up, feel free to contact us directly at 888-404-4363.
Tan says
What is it going to say if you are the father? And what is it going to say if you ARE NOT the father?
Admin says
Hi, Tan! You can read all about it here: http://dnatesting.com/what-do-my-results-mean/
Latrice says
What if you obtained samples from both child and alleged father about 4 months ago and kept results sealed and just sent them off 4 months later? Will test still show accurate results?
Admin says
Hi, Latrice. As long as samples have been stored in a cool, dry place, there shouldn’t be any problems with testing the DNA.
John Foreman says
How can I determine the difference between my daughter and son’s DNA test?
Admin says
Hi, John. On your report, the locus labeled AMEL is the sex chromosome. If it’s your daughter, it will be labeled X or XX. If it’s your son’s, it will be labeled XY because males have the Y chromosome.
Rose says
If the mother swabed only my mouth and never the child’s would you be able to tell if it’s only one person DNA
Identigene says
Yes.
Tammy Lea says
Would you be able to know if the mother swabs her mouth and not the child’s mouth?
HomeDNA Identigene says
If the child is a female, then no. DNA testing doesn’t identify age of participants…only the sex.
Christine says
What part of the swab do they test for xx and xy my daughter had a test done with her dad and my daughter only felt the tip touch her cheek, she has claimed that her step mum then run her wet finger around the other half of the swab would this have been picked up in the lab or would they just presume it can from the same xx after they test for sex
Identigene says
Hi, Christine. It’s not a matter of which part of the swab the DNA is extracted from, but whether or not the sample itself is enough to test. The technology is so sensitive and the technicians are so well trained that if any contamination had occurred they would have halted testing and asked for new samples.
Tasha says
If a son was tested and father but you think they used the same DNA for the son and father would the lab be able to tell and ca DNA be took off one swab placed on another
Identigene says
Hi, Tasha. The only two people who have the exact same DNA profiles are identical twins. So if someone used the same DNA for swabs that are supposed to be for two different people, then the lab would catch it and ask for new samples before issuing a report.
Trisha says
Do you test both mother and father or just the father?
Identigene says
Hi, Trisha. The lab fee for a paternity test includes the participation of both the mother and one possible father. The mother’s participation is not required, but it is recommended, due to the relatively rare instances where her DNA might be needed to strengthen results.
Patty says
Can this test also determine race and percentage of it like 23 if you ask for a more thorough explanation on results?
Identigene says
Hi, Patty. No, this test is a paternity test and not an ancestry test. It only answers the paternity question.
Sf says
Can a paternaity DNA test show anything else besides what it suppose to?
Identigene says
Hi, Sf. The short answer to your question is “no.” Paternity testing uses 16 genetic markers from what’s called “junk DNA.” This DNA does not code for anything specific, such as eye color, etc. When we do testing, the job for our analysts is basically to get a yes or no answer on the question of biological relationship only.
B says
(Re-posting question for clarification)
I was conceived via IVF in the late 1980s. My parents were told my dad’s sperm were “weak swimmers” so the doctor used both my dad’s weak sperm *AND DONOR SPERM* to conceive me.
I (female) have 2 older brothers: 1 brother was conceived with donor sperm (different sperm than mine); and 1 brother was conceived naturally and is my dad’s biological son.
Since I don’t know whether my dad or sperm donor is my biological father, and I have one brother who definitely IS my dad’s offspring and another brother who definitely IS NOT my dad’s offspring, what is the most efficient / effective way for me to determine whether my dad is / isn’t my biological father?
I’ve done 23andme testing, but no one else in my family has yet. Should I have my brother who is dad’s biological offspring do this testing, too? Or do I need to ask my dad to do it to determine whether he is my biological father? (I’d rather not have to ask him, but realize it may be necessary.)
I don’t know whom I need to or should ask to do testing: my possibly-biological dad, my definitely-half brother, or my possibly-half / possibly-full-brother.
Identigene says
Hi, B. The easiest, most conclusive, and most cost-effective way to determine paternity is with a straight paternity test: testing you and your dad. If he’s willing, that’s definitely the way to get the answer you’re looking for.
Dee says
Can a mother and daughter do a DNA test to make sure they are infact mother and daughter? How much would that be? Daughter is adopted no birth father or other family to test on either side.
Identigene says
Hi, Dee. A maternity test works just the same as a paternity test and costs the same too. You would just need to call our lab to set up the test.
Kristi says
what if you only use 2 of the dna swabs instead of 2 can that mess with your results
Identigene says
Hi, Kristi. The reason we ask for three swabs is to ensure we have enough DNA to test with. If you only use two, chances are good the lab will still have enough to test. If not, they’ll suspend testing and ask for more samples. It doesn’t affect results at all.
Becca says
If the possible fathers mother does the DNA test, without using the possible fathers dna, or the child’s mothers DNA, and the results come back 94 to 1, is it reasonable for the father to want another test? Or is most likely the baby is his?
Identigene says
Hi, Becca. A paternity test done with an accredited lab is going to be the most accurate…always. Much more so than a grandparent test done without the participation of the child’s mother.
Sara says
If the mother sends two swabs and the child (daughter) sends two swabs and the farther only sends one swab good this effect the results of whether or no the farther is the biological farther?
Identigene says
Hi, Sara. What matters is that the lab is able to extract enough DNA from all participants’ swabs to be able to conduct adequate testing. If they don’t have enough DNA, they will contact the person who ordered the test and send out swabs for additional samples. No worries!
Alexa says
If someone wants to determine paternity of the daughter but uses the sons dna is it shown on the results that it was in fact the boy and not the girl
Identigene says
Hi, Alexa. Yes, determining the participants’ sex is part of every paternity test. If the lab knows the child is supposed to be a female, but testing shows male, testing is suspended and new samples are requested before results are issued.
Brandon says
I swabbed myself and my daughter 4 months ago, at the time a man didn’t want to to take the test. Now another man wants to be tested. I kept me and my daughter’s swabs in a cool dry place. Can a test still be performed if i swab another man or would i have to purchase another kit?
Identigene says
Hi! Usually, swabs with samples can be viable up to 6 months, so you should be OK.
mary says
can it be determined that there was incest involved by only using mother and son dna?
Identigene says
Hi, Mary. Determining cases of incest is difficult, and you weren’t clear on who might be related to whom. If you want to know if the mother of the child is in some way biologically related to the father of the child, then the child’s DNA is no help: you need the possible father’s DNA.
Jackie says
I think my mother and father were siblings, my mother is deceased; Can the identagene test determine if my uncle is my father?
Identigene says
HI, Jackie. The in-store kit is not the right one for you, since that’s for a straight paternity test. I recommend you contact our parent company DDC directly and one of our experts can go into deeper detail with you and help determine the right type of test, if it’s even possible to do so. That number is 800-681-7162.
Kristi says
If the possible father of a child is either “Man A” or “Man B” and
(1) “Man A”is the father of “Man B”
(2) “Man A” is deceased
(3) Have dna swab of “Man B” and the child
Would there be a false positive result since “Man B” shares father / son DNA with “Man A”?
Identigene says
Hi, Kristi. That is possible, which is why we always (ALWAYS!) tell people to tell the lab when ordering the test that the other possible father is a close biological relation of the man being tested. When the lab knows this, they can test additional markers to determine paternity.
Steve says
For regular paternity test, proclaimed father’s and Child’s sample are provided.
As per my understanding, this test provides 99.9% probability for positive test result.
What if the possible father of child is brother (not a twin) of proclaimed father for which sample provided? Will this test be still positive, because as brother, they would share same DNA structure.
Or does need it additional test or sample of brother/mother of child?
Identigene says
Hi, Steve. If two alleged fathers are brothers, then they should both be tested if possible. If only one can be tested, then the mother should submit her DNA also and the lab must be notified ahead of time about the existence of a different close relative who may also be the father. That way, the lab can perform additional testing, if necessary. Brothers share 50% of their DNA, so notifying the lab is an essential step.
Shanice says
What If The Father Use 2 Swabs Instead Of All Four Can I Just Use Those 2
Identigene says
Hi, Shanice. We run every test twice, so he should use all four to ensure there is enough DNA samples to complete testing.
Ann says
We have tested DNA of our daughter, the father, and the mother twice at ancestry and twice it has said no dna found for my husband. I match her as the mother. I have only had sex with my husband and daughter looks exactly like her father and cousins. Is there a test that can help us find out what is going on. She has had multiple health issues.
Identigene says
Hi, Ann. Ancestry tests are not diagnostic, which is why the type of relationships found through ancestry testing alone cannot be used as absolute proof, either for peace-of-mind purposes or in court. The only way to find out for sure is to test your husband, your daughter, and you with an actual paternity test. As for physical appearance, that’s never irrefutable proof of a biological relationship. If you want to do an at-home paternity test, you can pick up our kit at CVS, Rite Aid, Walgreens, or Walmart. If you need results for legal reasons (such as inheritance benefits), call us to arrange a legal test: 800-344-9583.
Carry says
I shouldve worded that different . if a childs mothers brother was swabbed instead of the childs alleged father would that be detected that it was the mithers brother and not the childs alleged father?
Identigene says
Yes, most likely. If the child’s alleged father is indeed the biological father, the lab should give a 0% probability for the man tested with a notation that, although the man tested is not considered the biological father, that there is a strong likelihood that the biological father is a close relative of the man who was tested.
Scared says
If mother became pregnant by her cousin and had a daughter, would this paternity test work? Is mother and cousin’s DNA too close together that it would show in daughter’s DNA regardless? We can only obtain a sample of mother, cousin and daughter’s DNA.
Identigene says
Hi, Scared. What they need to do is tell the lab ahead of time that the mother and alleged father share a cousin relationship so that this relationship can be taken into account during analysis.
Toya says
I only stepped at one time on my boyfriend should I get a DNA test
Identigene says
All it takes is once! Yes, a DNA test is always a good idea, just to be sure.
Wendy says
Hi, I did a DNA test(23&me); found a guy who shares 50% DNA with me and the result says he is my birth father. But he has 4 brothers and he thinks he might be just my uncle. Can paternity test tell he is the father or the uncle?
Identigene says
Hi, Wendy. Yes, absolutely. Ideally, all the brothers would test. If only one or a few are willing, it’s absolutely essential that you tell the lab that there are other possible fathers, and that they are the brothers of the man being tested. You’re welcome to contact our parent company, DDC, if you have additional questions or to set up a test: 800-681-7162.
todd says
a friend of mine took a test as the father when he is the grandfather just to see if there is any percent possibility that will show up
whats the possibility??
Identigene says
A grandparent and grandchild share 25% of their DNA.
Charles says
I’m ordering a DNA test to get done on a women’s child that I believe to be mine.
If I send my mouth swab and she sends in her mouth swab instead of the childs.would the lab be able to pick up it’s a adults swab instead of a childs?
Identigene says
No. This test includes the sex gene to check for gender, but not age. If the woman’s child is a girl, there is no way to tell if the mother submits hers instead of the child’s.
Les says
If just an x is shown on a result
Under a male child’s name would there be a reason for this
A bit confused
HomeDNA Identigene says
Hi, Les. No, it should be an XY.
Les says
Can the alleged father submit his daughters swab under a boys name
HomeDNA Identigene says
Hi, Les. If the envelope states that the participant is a male but the test determines the sample is for a female, the lab will suspend testing and ask questions.
Les says
We have a test result and want to double check it but the alleged father is refusing
Could we retest the child and check the result with the one we already have to see if the child’s result matches the first one
Or do we need the alleged fathers again
HomeDNA Identigene says
Hi, Les. Just getting a new DNA profile from the child wouldn’t really tell you anything new. The alleged father can be compelled by a court to test again if it is deemed there is sufficient reason for a test.
Lee says
If one brother got a definite “no” from a paternity test (his and potential child’s dna, not mothers) is it still possible another brother could be the father. That brother is now deceased, so untestable.
HomeDNA Identigene says
Hi, Lee. Yes, it’s possible, since brothers only share 50% of their DNA. What you could do is test the child with one of the brothers’ other siblings, or a known child of the brother. You could also test the initial man again, but this time do an avuncular (uncle) test In any of the other possible tests I mentioned, it’s best if the mother(s) can test also. Hope this helps!
John says
Hello, I am wanting to do a paternity test on my son, I just want to be positive he’s mine. Problem is I do not want his mother to be upset with me or try to take him away from me, if I bring this to her attention. What do I do? Does the mother have to be swabbed in order to determine a paternity test? Or can I swab just my son and myself and still get accurate results? Please help me. Thank you.
HomeDNA Identigene says
Hi, John. You’re probably OK. In most cases, the mother’s DNA is not necessary for testing. However, we do recommend it in case it ends up being needed to strengthen results. This is why we include enough collection materials for her as well and include her participation in the lab fee.
Deborah says
What does “the likelihood that the alleged relative is the biological relative of the tested child is 38 to 1” mean?
HomeDNA Identigene says
Deborah, it means the chances that the person tested is related to the other person tested is 38 to 1. Those are not conclusive results and additional testing is needed.
Emma says
If a test by a company such as 23 & me, ancestry etc. revealed relationships to cousins of the supposed biological parent (no test taken by the parent), what would be the accuracy of such a test and should there be additional testing to confirm?
HomeDNA Identigene says
Hi, Emma. Those tests are fairly accurate at revealing possible biological relationships, but they are not accredited to confirm those relationships (and can’t be used in court, for example). It is recommended that the interested party test directly with the alleged biological parent to confirm.
Anonymous says
Hi if its a fathers dna test but can the mother swab instead will it come back positive?
HomeDNA Identigene says
A mother cannot substitute her DNA for the alleged father’s because the test checks the sex chromosome.
Daphne says
Thanks for explaining that DNA can be mislabeled or even contaminated, which is why it’s helpful to have the sex of the participant verified during the testing. My sister is pregnant and is not sure who the father is, so I’ve been helping her do some research about DNA testing and how accurate it can be. I’m glad I read your article because you helped me better understand DNA testing and feel more confident in its abilities.
Carly says
what if your mother got DNA for one guy and had me testing back in the 90’s, but didn’t have my “father” tested. She says the results said show that other man was my father. Is that truly accurate? Or would you need to take DNA from both men and compare them to mine to get a true comparison. This was done with myself and my sister, 10 years apart with 1994 and 2004 with DNA technology, saliva.
HomeDNA Identigene says
Hi, Carly. We don’t need both men’s DNA to get conclusive results on a paternity test unless those two men are close biological relatives (father/son or brother/brother, for example).
Lynn says
What if possible father and grandfather to the child are both deceased? Can you use possible great grandfather to the child for a DNA test?
HomeDNA Identigene says
It is better to test a relative closer to the child, if at all possible, like the alleged father’s sister/brother, or another known child of the alleged father. If the child is a male, and the great-grandfather is direct to the child through the male line only, then the lab can perform a Y-chromosome test to see if they are related.