Sibling DNA Testing — Full vs Half Sibling Relationship Testing

A sibling DNA test can be conducted for both legal purposes and personal knowledge. If you want results for your peace of mind, you can collect DNA samples in the privacy of your own home with our home-testing DNA kits. To use test results in legal matters, DNA sample collection must take place at an authorized location following a strict chain of custody.

Full vs Half Sibling DNA Test: This test is performed when two siblings share the same mother but want to know if they share the same biological father. If they share a father, they are full siblings. A Full vs Half sibling test can only be performed if both individuals are certain they share the same mother.

Half Sibling vs. Not Related DNA Test: This test is performed when two alleged siblings do not have the same biological mother but want to know if they share the same biological father. Samples are taken from both mothers and the two potential siblings to correctly identify the father's genes.

Understanding sibling DNA test results: Results are expressed as a probability percentage. A result of 90% or higher generally indicates the relationship is definitive. A result between 9% and 89% is considered inconclusive, and additional parties may need to be tested. A result below 9% generally indicates the relationship is not supported by DNA testing.

We are the most trusted sibling DNA testing provider nationwide, serving Oakland, San Francisco, Los Angeles, Sacramento, San Diego, and all major California cities, as well as clients in all 50 states. We follow strict privacy protocols to ensure your genetic information is never shared or sold to any third party.

Sibling DNA Testing FAQs