More DNA Tests

DNA Testing for Siblings (Brother or Sister)

Sibling DNA testing determines if two individuals share one or both parents. DNA Testing with a possible brother or sister can help answer paternity questions when the possible father is not available to be tested.

Half siblings share one parent. For example, a brother and a sister may share the same mother, but not the same father. Or, two sisters may share the same father, but not the same mother.

Full siblings share two parents. For example two adopted brothers or sisters might share the same mother and father.

When ordering your Sibling DNA Test, make sure you tell us which test type you need. IDENTIGENE DNA testing experts help guide you through the process and answer all of your questions—both before and after the test—so you can truly Test Assured.

Sibling DNA Tests can be used privately, for personal peace of mind, or can be made court-admissible when using a third party collector. IDENTIGENE helps make all the arrangements when you call.

How to Get a Sibling DNA Test (Brother or Sister)


1. Purchase your kit by calling 1-888-404-GENE (1-888-404-4363).

Test kits sold at the drugstore are intended for paternity testing only. If you purchased a kit at the store, we will apply the cost of your kit toward the final price of your grandparent DNA test.

2. Test at home or via one of our collection sites.

For at-home, private testing, IDENTIGENE will send you collection materials. We will arrange for your collection appointment (and send a legal DNA test collection kit directly to the collection site) when testing for legal purposes (such as immigration or child support).

3. Collect samples using simple cheek swabs.

Use the kit as directed and, with the safe and simple cheek swabs included in the kit, collect samples from the siblings and their biological mother(s) (optional).

4. Mail your samples to IDENTIGENE.

Use the postage paid return mailer provided in the kit. (For legal-purpose DNA tests, the collector will ship DNA samples directly to IDENTIGENE maintaining a documented chain-of-custody.)

Access results online in just 10 working days from the time your samples arrive at the laboratory.

IDENTIGENE Sibling DNA Tests are 100% accurate and can provide conclusive results, but some tests may prove to be inconclusive. At IDENTIGENE, we cannot guarantee and conclusive result, but we use extended panels and additional testing as needed to give the best possible chance to prove the full or half sibling relationship.

If you intend to use the Siblingship DNA Test results in court (a legal siblingship test), be sure to let us know so we can arrange for a third-party to collect the DNA samples. (Learn more about Legal DNA Tests.)

If you have any questions about DNA Testing for Siblings or other DNA Testing, please contact us (Monday through Friday, 9 AM to 6 PM ET).