‘Infidelity Testing’ is a service offered by certain providers that allows you to send them an item – an article of clothing for example – to be assessed for the presence of DNA traces. These tests can prove or disprove the presence of male or female DNA, and for an extra fee, they’ll tell you the number of unique traces found, and even discount you or your partner as the source.
The test assumes you believe your partner has had close contact with a third party, and that this third party’s DNA has found its way in or onto the item in question.
Are the tests accurate?
It depends. The success rate of DNA extraction from in or on an item is 25-99%, depending on the type of item that’s being analysed. For assessing items of clothing the success rate of DNA extraction is around 50%.
Are the tests legal?
It depends. It’s illegal to possess an adult’s DNA sample with the intent to test it without that adult’s consent. Therefore, if you suspected that your partner had been in close contact with a third party, and you wanted to test a piece of your partner’s clothing to look for traces of that third party’s DNA; your partner (and that third party) would have to sign a consent form.
Be warned, providers that offer this test may imply that you can test your partner’s item in secret, but this would be illegal as you’re intending to test for DNA that’s not your own, without the suspected owners’ consent.
If the adult’s sample is being tested outside the US, do I still need their consent?
Yes, possessing an item with the intent to test for DNA that’s not your own is breaking the law if you do not have the suspected owners’ consent.