Between 2015 and 2016 the twins were part of a year-long mission to the International Space Station, with Scott spending the year in space and Mark on the ground functioning as the control group.

Checkout the crazy things these twins do that you never knew! Elizabeth and Rose Conway shared the secrets behind the life of an identical twin.

The fitness community has long debated whether a high-fat or high-carb diet is the ultimate fuel. Two identical twins put the ...

In a closed adoption, there is no contact between the biological parents and adoptive families— but fate had other ideas.

Find out everything you've always wanted to know about identical twins – from how they form to what makes them unique.

If you were old enough to watch the news or read the paper back in the late 1990s, you very likely remember Dolly, the cloned sheep. Born in 1996, the researchers responsible for cloning her kept it ...

When identical twins Marielle and Mireille Landry were growing up, they often daydreamed about their birth mother. What did she look like? Did she still think about them? “We both had so many ...

PRESTON, Minn. — The identical twin sister accused of trying to take the blame for her sibling by lying to investigators after a deadly Amish buggy collision in southeastern Minnesota has ...

Kaine and D-Roc of the Ying Yang Twins tell PEOPLE about making music in Atlanta and celebrating their legacy while paving the way for their future.

Stem cell engineering and CRISPR were used to create mice with two male parents. Could we use this technique on humans?