Twin Zygosity Testing

Twin Zygosity DNA Testing in Canada

Twin zygosity testing is a DNA test used to determine whether twins are identical (monozygotic) or fraternal (dizygotic). While identical twins share nearly 100% of their DNA, fraternal twins are genetically similar to regular siblings.
Twin zygosity DNA testing analyzes genetic markers from each twin to determine whether they originated from:
• One fertilized egg (identical twins), or
• Two separate fertilized eggs (fraternal twins)
Knowing whether twins are identical or fraternal can be important for:
• Genetic and inherited health conditions
• Organ or tissue compatibility
• Medical research and diagnostics
• Family history and ancestry records

There are two types of DNA tests available: legal zygosity testing and private zygosity testing. Our fully accredited laboratory follows the same rigorous high-quality standards when processing both legal DNA tests and private DNA testing cases.

A legal Twin Zygosity DNA test is required when results must be used for official or legal purposes. This type of testing follows a strict chain-of-custody process and is accepted by Canadian courts, government agencies, and immigration authorities.
Common reasons clients request court-admissible twin zygosity testing include:
• Medical and health-related planning
• Legal or insurance-related documentation
If you need a legal DNA test done, you can choose to come into one of our convenient testing locations across Canada or have a mobile unit sent to your home (in select areas). During the collection process, the individuals tested are positively identified through photographs and government-issued identification. Certified DNA specialists collect the DNA by doing a simple and painless mouth swab from the inside of the cheek. All information is documented on a Chain of Custody, which ensures all test results are accredited and legally admissible.
Once received at our laboratory, your results will be ready and sent via email within 5 to 7 business days, or for an additional $100.00 you can add a rush analysis which ensures your results are completed within 3 to 5 business days.

Private Twin Zygosity DNA tests are treated the same as legal DNA tests in the laboratory, and they’re just as accurate. The difference is you can collect the DNA samples yourself in the comfort of your own home. You will receive your kit in the mail along with easy-to-follow instructions, collection envelopes, mouth swabs and a client ID form. We also include a self-addressed envelope so you can send back your samples for testing.
✔ No court involvement
✔ Confidential and private
✔ Fast results
Once received at our laboratory, your results will be ready and sent via email within 5 to 7 business days, or for an additional $100.00 you can add a rush analysis which ensures your results are completed within 3 to 5 business days.

If you have further questions, please view the Frequently Asked Questions page or contact a Certified DNA Specialist toll-free at 1-877-477-5661.