“Uh oh. I think I messed up my paternity test.”
Our customer-service specialists often hear this statement from clients who call in, worried about whether or not the samples they submitted for their at-home paternity test or other relationship analysis might have been contaminated.
When you order a test, you and the lab form a partnership in the proper handling of these samples. As a highly-accredited laboratory, we take our responsibility seriously and have strict processes in place to ensure samples are not contaminated at the lab level. As a participant in the test, your job is to get your samples to the lab in the best condition possible.
Collecting DNA with cheek swabs is easy and painless, but do it with care.
DNA collected via cheek swabs is every bit as effective for testing as a blood sample. The process involves vigorously rubbing the inside of the cheek for 30-60 seconds for each swab included in the kit to ensure enough cells are collected for testing. So how might samples for a paternity test get contaminated?
1. Eating, Drinking, or Smoking before Swabbing
All participants in a paternity test should refrain from eating, drinking, or smoking for one hour prior to swabbing—this is also true for nursing infants. Although having foreign residue in your mouth won’t change your DNA, it can definitely affect the quality of the samples by degrading them, making it difficult or impossible for robots at the lab to extract usable DNA from the swabs.
GOOD NEWS: This type of contamination doesn’t affect the results of your paternity test because the lab simply stops testing and asks for new samples before proceeding with analysis. New testing materials are sent to you at no charge.
BAD NEWS: It’s a source of stress for you because your results will be postponed and you have to wait a little longer.
PREVENTION TIPS: If one of the participants eats, drinks, or smokes prior to swabbing, just delay swabbing for an hour.
2. Cross-Contamination during DNA Collection
To maintain the swabs’ integrity, do your best to avoid the following:
- Handling the soft ends of the swabs
- Dropping swabs
- Allowing the heads of swabs from two different people come into contact with each other
- Putting swabs from two different people in the same envelope
GOOD NEWS: If contamination occurs as a result of any of these actions, the lab will catch it and ask for new samples.
BAD NEWS: Again, you have to wait longer for results if the lab asks for DNA recollection.
PREVENTION TIPS: Handle swabs with care and follow all kit directions.
3. Mailing Wet Envelopes or Re-Using Plastic Packaging
Wet Envelopes
It’s not at all unusual for a little excess saliva to get mixed in with cheek cells when collecting DNA for a paternity test. As a result, the sample and even the mailing envelopes may become a little wet. If mailed while damp, packaging could tear and swabs can become contaminated.
GOOD NEWS: DNA samples can simply be collected again.
BAD NEWS: There is a delay in issuing results.
PREVENTION TIPS:
- The swabs for a paternity test are designed to collect cheek cells—not saliva. Be sure to only swab the insides of your cheeks and avoid gum areas
- If a swab is “too wet,” hold the swab up and wave it in the air for 60 seconds to dry it a bit before placing in the paper sample envelope
- If an envelope still gets a little wet, lay it on a clean counter and allow it to air-dry prior to mailing
Re-using Plastic Packaging
DNA is organic material and is therefore susceptible to becoming moldy under adverse conditions. Mold degrades DNA on a swab extremely fast, and this kind of contamination makes using the sample for testing impossible. If you put swabs containing DNA back into the plastic packaging the swabs came in, the sample can’t “breathe” and the consequence is almost always rapid mold growth—even if you mail samples off right away.
GOOD NEWS: New DNA samples can be collected.
BAD NEWS: You have to wait longer for results.
PREVENTION TIPS: Once you’ve collected the DNA, make sure the swabs have been air-dried as much as possible and then place them in the paper envelopes provided in your kit.
Final Thoughts about Swab Contamination
It’s important to remember that swab contamination can never “change” the results of a paternity test or “change the DNA.” So there’s no need to worry! If contamination occurs, the lab always catches it, and the worst that can happen is the lab will ask for samples to be collected again. Just be sure to carefully follow all instructions that come with your paternity test, and feel free to reach out to us if you have any questions or concerns.
Hi, I did the paternity test and it was a buccal and I ate and drink 5 min before my test and I didn’t get the right results. Can you please do something about it.
Hi, Patience. Eating and drinking before swabbing cannot change the DNA or change a test result. The only thing that can do is adversely affect the quality of the sample. If you were issued a results report, then eating and drinking was not an issue.
I once did the paternity test, and it was taken to gamany and the result came one month later, I didn’t get the right result. Can you please do something about it.
Hi, Prudence. For any questions about a past test, contact us directly at 800-831-1906 during business hours.
How many marker do your test
Hi, Makeba. For paternity we test a minimum of 20 + the sex chromosome.
My child is only a year old and they kept biting and licking the swab while I was swabbing her cheeks, is that Going to interfere with my results ?
Hi, Devin. As long as you also got enough cheek cells on the swab, biting and licking won’t make a difference.
Can the alleged father’s mother take the dna test to determine paternity
Hi, Sylvia. Yes, we do grandparent testing. Receiving conclusive results is much more optimized when the mother of the child also contributes her DNA. For more info, please contact one of our DNA specialists for a free, no-obligation consultation at 800-681-7162 (M-F, 8 am to 8 pm Eastern).
If a newborn was tested but saliva was collected and swab didn’t touch the cheek can it alter the results?
Hi, Treva. No, it won’t alter the result, but there may not be enough DNA in the saliva to complete the test. The reason we ask for cheek cells instead of saliva is because they are DNA-rich. If it turns out there is not enough DNA to complete testing, the process is temporarily suspended and the lab will ask for new samples. If there is enough DNA in the saliva after all, then you’ll be issued a results report.
The representative I spoke to on the phone knew how far along I was. But when I gave a blood sample my technician was wondering if it was too early. Would I have to pay for another test if this is true?
Hi, Ash. We can do testing as early as 7 weeks. If it turns out there is not enough DNA in your blood sample to complete testing, we would schedule another blood-draw appointment in 2 weeks. And no, there is no extra charge.
Hi I currently done a swab but a lot don’t add up and I’m feeling abit confused I understand a dna cheek swap is very accurate my results came back that I am not the father due to 6 out of 14 cells not being the same as me but I’m confused on how they came up with a result on that amount ?
Hi, Reece. You can learn more about the results of a paternity test here: https://tests.dnacenter.com/blog/understanding-paternity-test-results/
How soon will you call back of more dna is needed
You are notified via email or text immediately.
Can a swab be used on a drink to make someone the father
Hi, Ricky. No, that method would not provide enough DNA to conduct a paternity test.
We did a swab Dna test but did not swab my daughter for the allotted time? Will the test still be accurate?
Hi, Ashley. If a test report is issued, then the delay in submitting swabs wasn’t an issue. If the daughter’s swabs were contaminated because they were kept too long prior to sending them to the lab, this doesn’t affect results, no report is provided until new swabs are obtained.
Hi, I ordered dna test today. How long will it take for me to receive my kits? I live in Michigan and my Dad is in Arizona.
Hi, Brittaney. If you didn’t choose express shipping, it takes 5-10 business days for USPS to deliver kits.
We took the samples but waited 2 weeks to send them in. The results came back 0% probability,is that a normal result? Could the samples be contaminated?
Hi, Becca. DNA can remain viable on swabs for up to 6 months if kept in a cool, dry place. Had the swabs been contaminated, then the lab would have suspended testing without issuing a result and requested new samples. The report said 0% probability because the DNA data from the swabs did not support a biological relationship.
I was only able to collect 2 swabs for one of the people being tested. Can I send the 2 swabs for the one person and the 4 swabs for the other person?
Hi, Nicole. Hopefully there is enough DNA on the two swabs to complete testing. If not, we’ll reach out and request more.
Hey Melissa. Im in the same situation just want to know if there was enough dna on the two swabs u sent? Thank you!
How long does a Paternity takes before no good check the blood test
Hi, Alicia. I’m not sure I understand your question?
If drinking alcohol will it mess the results up?
Drinking alcohol prior to swabbing will not change the DNA, no.
My son was mouth swabbed for his paternity test. If I would’ve transferred my saliva on the inside of my sons cheeks, would that have altered the paternity test results?
Hi, Ivy. If for whatever reason the lab detects two separate people’s profiles on one or more swabs, testing is immediately suspended and results are not issued until fresh samples are obtained.
That does not answer my question. Let’s say I was not swabbed for this test because I refused. Then what?
Your question was about adding DNA to someone’s mouth and I believe I answered that. As for this question, if you refuse to participate in a court-ordered test, then it is very possible the court would rule in the other party’s favor.
How would the lab detect my saliva if they did not swab me though? Is there not a yes or no answer on the matter if I would’ve inserted my saliva on the inside of my child’s cheek before his mouth swab would that have altered the Paternity test results?
Can a swab DNA results be inconclusive?
Hi, Patricia. I assume you are talking about a paternity test, correct? There is no good reason for any accredited lab to provide inconclusive results for paternity nowadays. If the standard panel doesn’t yield a conclusive result, then the lab can test additional markers or ask to add the mother’s DNA to the test. Whether the sample is swab or blood or other type of sample, this holds true.
I submitted swabs today taken at home. The rep I talked to said we could make our own swabs by cutting off the end of a qtip we didn’t use, and then place them in an envelope. I’m worried that was incorrect? He won’t give me another sample so I’m hoping this was an appropriate way of doing it… it’s time sensitive for us and we didn’t have time to wait for a kit to be shipped to us.
Hi, Korri. It should be just fine. No worries!