Sibling Tests

At dadcheck®silver we conduct scientific personal information sibling DNA tests to determine if two or more individuals are related as full or half-siblings.

A sibling DNA test may be performed instead of a paternity test when the alleged father is deceased, unavailable or unwilling to take part but the child’s possible full or half-sibling is available.

When ordering such complex tests, we recommend that once the order is placed, you call us to explain the case background to ensure we are testing the correct scenario.

How accurate are sibling DNA tests?

Every one of us is unique. This uniqueness comes from our genetic code, which we have inherited equally from our biological mother and biological father. All siblings will share common genetic markers with each other which they have inherited from their biological parents. If we analyse the samples of possible siblings, we would expect to find these common maternal or paternal genetic markers which can in turn be used to determine if individuals are related.

For such 'complex' tests, we would strongly recommend that the mother(s) as well as the children participate in the testing as this really helps with the interpretation of the final results and makes the results much more conclusive.

Occasionally a biological relationship may exist between two (or more) tested people, but it cannot be detected because of the relatively low amount of DNA shared between the tested individuals.  This would be the one thing we would like to make you aware of before embarking on such as test.

A paternity DNA test would give the most conclusive results, but this can only be carried out if we can obtain DNA samples from the alleged father.

Which type of test do I need?

If you already know that you share one common parent, usually the mother, and would like to establish if you also share the same biological father, then the question is, are we full or half-siblings?  Please select child 1 and child 2 test if there will be no mother participation or 2 children and mother if the mother is available to participate.

If you are looking to establish if you share only one common parent, usually the father, and have different biological mothers, this would be classed as half-sibling versus unrelated.  Please select our half sibling test (2 children 2 mothers).  Though we prefer at least one of the known mothers to participate as explained above, you can select ‘not participating’ if they are unavailable for testing.

Relationship DNA testing can be a life-changing event and we would recommend that before ordering a test you think carefully about the potential outcomes and have considered if testing will be in the best interests of those involved.

Please note that this at-home test is for personal information only - this means that the results will not be accepted in UK courts by the Child Maintenance Service or any other legal body.