Cousin testing can show whether two people are biological first cousins – first cousins share a set of maternal or paternal grandparents, but are not siblings. Testing providers need a cheek swab sample from the ‘alleged’ cousins and the samples are then compared to see if there’s a genetic match.
On purchasing, the provider will send you a testing kit with everything you need to take the samples. You can take the samples at home and after you send the kit back, they’ll be in touch with the results a few days later. You can choose how you are contacted, with email generally being the quickest service. Some providers offer express services but these often come with extra fees.
Look out for companies selling cheap kits. That’s exactly what they are – just the kit and no testing. Providers then charge more to actually run the test when you return the samples.
’Peace of mind’ or ‘legal’ test?
There are two types of service for cousin testing: ‘Peace of mind’ tests and ‘legal’ tests – legal tests are court admissible. The science behind the tests is exactly the same – the difference is that for court admissible tests, somebody official needs to watch them being taken so the court is assured that the samples came from the right people. Court admissible tests also require that the samples be handled securely all the way to the lab.
Are the tests accurate?
The tests are accurate, but not as accurate or as straightforward as paternity testing because cousins are less closely related. The tests compare DNA from both parties at certain ‘DNA locations’ to establish a genetic match. Most providers check 16 locations, some check up to 68 which improves the accuracy but which costs more.
What if the cousins to be tested live far apart?
Some providers allow you to have the different parts of the test sent separately to those providing samples. All the kits are labelled so they can be matched back at the laboratory.
Watch out for VAT and hefty postage being added at the checkout. Some providers with offices in the UK will use labs overseas, so if having your samples tested in the UK is important to you (and the provider’s website isn’t clear) check out our listings for these details.