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Seattle Epidemiologic Research and Information Center (ERIC)


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Welcome to the Vietnam-Era Twin Registry Website

The Vietnam-Era Twin (VET) Registry is a United States Department of Veterans Affairs (VA) resource that was originally constructed from military records and has been in existence for almost 30 years. The VET Registry is a closed cohort composed of approximately 7,000 middle-aged identical and fraternal male twin pairs both of whom served in the military during the time of the Vietnam conflict (1964-1975). It is one of the largest national twin registries in the US and currently has members living in all 50 states. Initially formed to address questions about the long-term health effects of service in Vietnam, the Registry has evolved into a resource for genetic epidemiological studies of mental and physical health conditions. Several waves of mail surveys, telephone interviews, in-person data collections, laboratory testing, and secondary data analysis studies have investigated and collected a wealth of health-related information on Registry twins, referred to as members. In addition to twins, selected adult offspring of twins and the mothers of those offspring are also VET Registry members. The non-twin groups were added to the Registry in the late 1990s as part of a set of VET Registry family studies.

Information about Selected VET Registry Research Studies

Veterans and the Public

Visit the VA Research and Development Homepage for Research Highlights and Featured Content to learn about some of the research being done by VA researchers. Browse through the Programs section of the site to find out about the many different research programs throughout the country or if you would like to learn about participating in a research study.