Adult Twins

Resources for Twins

Inclusion in this list does not constitute an endorsement by the Washington State Twin Registry. If you know of a resource you think we should include here, please send an email to

For Twins Who Have Lost Their Twin

  • Twinless Twins Support Group
    A unique support group that helps twinless twins “heal by helping” other twins.
  • The Lone Twin Network
    The Lone Twin Network is a support group run by and for lone twins, whose loss has occurred at or around birth, in childhood or during adulthood.

Other Resources for Twins

  • wants to prepare twin parents for the task of raising two well-adjusted, independent children. We want moms and dads around the world to have loads of fun in their role as parents of twins, while still having an outlet to discuss concerns and anxiety in relation to becoming or being a twin parent. was launched by journalist Kate Phillipa Clark, who is an identical twin.


Below are some links to educational videos about topics related to twins. We hope you find them interesting and enjoyable. If you have watched an educational video about twins that you would like to share, please email us.

Beyond our genes: Identical with one big difference

“Twin sisters Kristin and Maren Hallenga are the founders of breast cancer awareness charity CoppaFeel! Following Kristin’s diagnosis with secondary breast cancer in 2009, they made it their mission to ensure other young people don’t find themselves in a similar situation to Kris; where they’re told the cancer cannot be cured because it was found late. Kristin has been tested for the known breast cancer genes but is not a carrier, yet Maren still stands a slightly higher chance of being diagnosed with the disease. These twins show continuous strength and determination, working tirelessly on raising awareness of breast cancer among young people throughout the UK.”


“Hank & his clone Circus Hank explain the power of epigenetics, which studies the factors that determine how much or whether some genes are expressed in your body.”

Epigenetics and the influence of our genes

“Because we want to understand what genes are required for blood vessel development, Courtney Griffin studies certain enzymes that help turn genes on and off. These enzymes are specifically involved in relaxing DNA that is normally tightly coiled up in our cells.”

Identically Different

“Tim Spector is a Professor of Genetic Epidemiology and Founder of TwinsUK. His talk challenges the current genetic dogma explaining why identical twins are far from identical and how environmental factors interplay with our genes to shape our health and identity.”

Twins: Is it all in the Genes?

“Dr. Nancy Segal has studied reunited twins for more than 30 years. With Lisa Ling acting as her research assistant, together they interview twins Linda and Doreen, who spent 35 years apart. The results of their interviews will help science understand the effects of nature vs. nurture on traits present in each twin.”

The Year-Long Twin Astronauts Experiment

“Astronauts Scott Kelly and Mikhail Kornienko will soon undertake a historic, record-breaking mission: to live in space for an entire year. And scientists will have some extra help studying the effects of this extended stay on the astronauts — Kelly’s twin brother Mark!”