Sibling DNA Testing


  • Just £199 for next day results, or upgrade to same day results for an extra £70 
  • The UK’s fastest DNA sibling test. Why wait?
  • Guaranteed results or your money back
  • Award-winning UK laboratory: Queen’s Award for Enterprise in Innovation
  • Trusted to provide DNA testing to ITV The Jeremy Kyle Show and BBC Family Finders

The UK’s best-selling home DNA sibling test from £199

£269 Same day results

To receive your results the same working day, click here.

£199 Next day results

To receive your results the next working day, click here.

A guaranteed result or your money back

At AlphaBiolabs we understand that the reason you have ordered a Sibling DNA test is to get an answer. However, not all DNA tests are conclusive, and therefore you may not get a decisive answer to your question.

It is the industry’s best kept secret that for most laboratories, sibling testing can be up to 40% inconclusive. This means that four people in every 10 do not get the result they have paid for.

At our award-winning DNA laboratory, we have been able to reduce the inconclusive rate down to 24%, meaning that one in four people do not get a definitive outcome.

This is still not acceptable at AlphaBiolabs and with this in mind we have launched our guaranteed result or your money back promise. For every customer using our service and not getting a conclusive result, we will refund the price of your Sibling DNA test, guaranteed. Please note, sibling tests bought via third party retailers are not included in this guarantee.

Four easy steps for your DNA sibling test

Buy your collection kit

Collect your cheek cell DNA samples

Post back to our laboratory

Receive your results by email

DNA sibling testing

Order a (guaranteed results) sibling DNA test for just £199 with next day results or you can upgrade to same day results for an extra £70.

AlphaBiolabs uses DNA technology to establish whether or not brothers and sisters have the same father or the same father and mother.

Our sibling DNA test has an accuracy rate of 100%. We can perform the sibling analysis without any samples from the mother or father.

We use statistical analysis to evaluate the amount of DNA shared between the individuals tested to deduce a biological relationship. For example, full siblings usually have more DNA in common than half-siblings, while half siblings normally share more DNA than unrelated persons.

Why is this DNA sibling test different?

Unlike a paternity test which will always provide a conclusive result, sibling DNA testing is different. When a sibling test is conducted, the DNA laboratory will determine the genetic profiles of the alleged siblings.

Based on the genetic material shared by each sibling, a sibling DNA index or likelihood ratio is calculated to determine the most likely relationship.

A likelihood of greater than 10 supports that the tested individuals are related as siblings, either full or half; whereas a likelihood of less than 0.1 does not support this. A likelihood which falls between 0.1 and 10 is considered inconclusive, which means a relationship cannot be determined, based on the statistical probability obtained from the analysis.

The higher the value of the sibling DNA index, the greater the likelihood that the two individuals are true biological siblings. It is possible to analyse two individuals to determine that they are more likely to share two common parents versus one common parent (i.e., they are full siblings sharing a mother and father) or that it is more likely that they have one parent in common versus them being unrelated (i.e., that they are half-siblings, with a single parent in common).

How we do our DNA testing

We utilise the most up-to-date DNA testing technology to ensure the reliability and accuracy of our genetic testing. We were the first UK laboratory to offer accredited 25 marker DNA testing and retest all our exclusion results.

We can send your DNA sibling test kit direct to an address of your choice using discreet packaging.

If you require a second DNA kit to a second shipping address, you can select this option at the checkout.

Our sibling test kit includes mouth swabs to be rubbed gently and painlessly on the inside of the cheek, so it is not a problem if anyone involved is scared of needles.

How does Same Day DNA Results Work?

To ensure Same Day Results, your samples need to reach our laboratory by 10 am. For this reason, we strongly advise you use the special delivery before 9 am service from Royal Mail. Your DNA results will then be emailed to you from 4.30 pm the same day.

How does Next Day DNA Results Work?

To ensure Next Day Results, your samples need to reach our laboratory by 10 am. For this reason, we strongly advise you use the special delivery before 9 am service from Royal Mail. Your DNA results will then be emailed to you from 4.30 pm the following day.

Sibling test support service

How to take a DNA sibling test

We recommend that you watch the video above where clinical psychologist Lisa Marsland talks about the issues that may arise from taking a DNA test.
Learn how to take your DNA samples at home using one of our DNA test collection kits from the comprehensive video above.

Enclosed in the test kit:

  • Peace of Mind DNA test request/consent form
  • Full instructions on how to take the DNA sibling test and return the samples back to us
  • A self-addressed envelope to send your DNA test samples back to us
  • Three DNA sample collection swab packages containing two swabs in each package.
  • Individual DNA test sample envelopes for three people

If you only want to test two siblings without any samples from a parent, only use two of the swab packages. If you want to test more than two siblings, you can add extra people to the package when ordering and more swabs will also be provided in the test kit.

Buy your DNA testing kit here today

Buy the fastest, most accurate DNA Sibling test here.