The UW Twin Registry is an ongoing database of twins who are interested in participating in research studies. Initially, potential twin pairs were identified by the State of Washington Department of Licensing (DOL). In Washington State, driver license identification numbers are based on a person’s last name, first and middle initials, and date of birth. Given this formula, both members of a twin pair might potentially receive the same driver license number. To avoid issuing duplicate numbers, the DOL asks every new license applicant if s/he is a member of a twin pair.
In September 1998, our group initiated the development of a population-based twin registry by negotiating with the Washington State DOL and the Washington State Attorney General to obtain access to the DOL records needed to construct such a registry. Access is possible because state legislation in Washington permits state agencies such as the Washington State DOL and UW to share information. Since 2002, the University of Washington (UW) Twin Registry has been receiving the names, contact information, and demographic characteristics of individual twins. Information on new individual twins is forwarded to the UW Twin Registry on a weekly basis.
In October 2009, the UW Twin Registry received a Grand Opportunity award from the National Institutes of Health to support a massive expansion. As a result of this award, the UW Twin Registry was able to identify twins through the renewal system for Washington State driver licenses and state IDs. The addition of the renewal system to the existing system (which identifies twins who are new to driving or new to Washington when they apply for their initial in-state licenses or IDs) significantly increased our recruitment efforts, doubling the size of the Registry in just two years.
In 2013, we began enrolling volunteer twins who contacted us with interest about joining. Additionally, we received approval to begin recruiting twin children. The UW Twin Registry continues to add new twins on a monthly basis.