Twins can make an important contribution to research. You are eligible to participate in the Washington State Twin Registry if both you and your co-twin agree to participate. If you are eligible, you and your co-twin will be asked to complete a brief questionnaire. You may be contacted to take part in specific studies. Participation in these studies is voluntary.

Frequently Asked Questions about Joining the Registry

Did you or your twin already receive an invitation to join?

The invitation sent by email or snail mail contains the link to complete the questionnaire online. Please do not use this form, as we already have your information. If you lost the link and/or your ID number, please call the Twin Registry at 1.833.432.8720 or email us at ws.twinregistry@wsu.edu.

Under 18 or a parent of twins? Click here.

To receive an invitation to join the Twin Registry, please complete the following form. We will send an email with a link to complete the enrollment survey. We must receive a survey from both you and your twin to enroll you into the Registry. For more information, please call the Twin Registry at 1.833.432.8720 or email us at ws.twinregistry@wsu.edu.