Direct-to-consumer DNA testing kits offer insights into ancestry and health predispositions. Many individuals acquire these kits but may not use them immediately, raising questions about their shelf life. Ensuring sample integrity is crucial for obtaining accurate results from these personal genetic tests.
Understanding Kit Expiration
DNA testing kits do have an expiration date, usually printed on the kit packaging or collection tube. While human DNA itself does not expire, the kit components designed to preserve a collected sample are time-sensitive. These expiration dates ensure the chemical reagents and stabilization solutions remain effective in protecting the DNA from degradation.
How Kit Components Degrade
The stabilization solution inside the collection tube is designed to prevent bacterial growth and protect the DNA from enzymatic degradation once a sample is provided. Over time, this solution can chemically break down or lose its buffering capacity, compromising its ability to maintain the sample’s integrity. The collection tube itself, often made of plastic, can also degrade, potentially leading to compromised seals that allow moisture or contaminants to enter. Even the swab or collection device can degrade, affecting its ability to collect sufficient cellular material. Environmental factors such as exposure to extreme temperatures, humidity, or direct sunlight can accelerate the degradation of these sensitive kit components.
Consequences of Using an Expired Kit
Using an expired DNA kit can lead to several practical issues, primarily affecting the laboratory’s ability to process the sample successfully. If the stabilization solution has lost effectiveness, the DNA sample may degrade before reaching the lab, making extraction difficult or impossible. This often results in the lab being unable to obtain sufficient DNA for analysis, leading to invalid or inconclusive results. In such cases, the testing company will notify the user that the sample could not be processed, requesting a new sample, which can cause delays and potential costs for a replacement kit.
Best Practices for Kit Storage
To ensure a DNA kit’s longevity and effectiveness, proper storage is important before sample collection. Store the kit in a cool, dry environment, away from direct sunlight or areas prone to extreme temperature fluctuations, such as window sills or uninsulated garages. Keeping the kit sealed in its original packaging until ready for use provides additional protection against environmental factors. Verify the expiration date printed on the kit upon receipt and before use to avoid potential processing issues.
What to Do with an Expired Kit
If your DNA testing kit has passed its expiration date, contact the customer service department of the DNA testing company. Many companies have policies regarding expired kits, often offering replacements at no or reduced cost. Using an expired kit is not recommended due to the high likelihood of sample degradation and processing failure. If a replacement is not feasible, responsibly discard the expired kit instead of submitting a compromised sample.