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    Ways That DNA Test Samples Get Contaminated

    All that’s required for most DNA tests today is a simple cheek swab or saliva sample. 

    Sounds simple enough, right? It’s important to take the proper precautions to ensure your DNA sample doesn’t get contaminated. 

    After all, you’ve shelled out the money for your DNA testing kit and you want accurate results. 

    Therefore, you’ll need to ensure you understand how to provide a sample of your DNA properly. 

    Keep reading to learn more about DNA sample contamination.

    Smoking, Drinking, Or Eating Before Sample Collection

    Common everyday activities may prevent you from getting a truly accurate DNA sample during your swab or saliva sample.

    If you’ve just enjoyed an afternoon snack and are thinking about getting your DNA sample right after, you may want to pump the breaks. 
    While food may not ruin your DNA sample, it can distort it. 
    If the DNA testing company can’t accurately read your results, you’ll have to restart the process.

    To keep your sample intact, stay away from food, drinks, and smoking one hour before you collect your sample. 

    It’s a small price to pay for peace of mind knowing you gave a clean sample, free of contaminants. 

    Spitting Instead Of Swabbing

    Be sure to read the instructions of your testing kit carefully. Some people have a habit of mixing up swabbing and saliva samples, which is a problem as they’re quite different. 

    DNA tests that require a cheek swab extract DNA from cheek cells that supply a good amount of high-quality DNA.

    If you spit on your swab, instead of sliding it on the inside of your cheek, the testing company may be left without enough DNA to process your results. 

    The key is to read the instructions carefully and be sure you understand them before proceeding with your test.

    It should be relatively easy-to-use and straightforward. Just take your time and you’ll be able to get a quality sample.

    Wet Envelopes

    Whether your DNA testing kit requires a saliva sample or a cheek swab, things could get a little messy. 

    It’s very important to carefully follow instructions when inserting your sample into the envelope. 

    If the envelope is made of paper material, moisture from the sample can cause it to rip in transit. 

    This in turn would render the sample unreadable. 

    To avoid this problem, try air drying the sample before you return it to the envelope. 

    If the envelope still gets a little wet, not all hope is lost. 

    Let it air dry on the counter, and once it’s dry, you can safely mail it back to the company.

    Cross-Contamination Of Samples

    Many families are interested in doing DNA tests together. 

    It’s a unique bonding experience to get your results around the same time, be able to compare the results together and learn about similarities and differences across family members. 

    If you and another member of your household decide to take a DNA test together, be sure that each test is kept separately. 

    Mailing the tests back in the wrong envelope, or in the same one, can cause contamination and inaccurate results. Each tester will have a test and an envelope, so be sure to keep them organized and clean as you complete your tests.  

    As your results include important health information, you’ll want total peace of mind that your test is yours and hasn’t been contaminated.

    Certain Medical Procedures

    Some medical procedures introduce another person’s DNA into your body. 

    These aren’t so common and are often related to more serious health situations that require a blood transfusion or bone marrow transplant. 

    The bad news is that it may be more difficult to perform a test once you’ve undergone these procedures. 

    On the bright side, it might still be possible to perform an accurate DNA test.

    Let the lab or company you’re testing with know about your specific medical history. They might still be able to test your DNA sample. 

    If they find that the procedure you’ve undergone is interfering with the results, they’ll let you know so you can avoid any confusion or inaccuracy. 

    Reused Packaging

    Your DNA test will come with specific instructions for collecting the sample. You’ll also be provided with all the materials you need to collect a quality DNA sample. 

    If you notice something in your DNA testing kit package is missing, notify the company immediately. All tools for collection should come completely sealed to avoid contamination.

    If you don’t follow the instructions and you put your sample back in a used package, that package may become wet. 

    This may not sound like a huge deal, but the moisture from your saliva can cause mold to grow while your sample makes its way to the lab. 

    This can be highly problematic for reading results. 

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    DNA testing today is a relatively straightforward and easy process. 

    Be sure to read the instructions carefully before starting and follow it step-by-step during collection. 

    Taking the time to do this process right the first time around will save you time and money, and help you avoid any inaccurate results. 

    With a little patience, you’ll be on your way to receiving exciting results regarding your heritage, ethnicity, and health.