Twins in space? Or more correctly, one twin in space – and one twin on earth. NASA’s novel program featuring identical twins Scott and Mark Kelly has garnered much interest in the media of late. This unique twins study involves studying two genetically identical individuals – living in different environments, earth and the NASA space station for one year.

At the Australian Twin Registry, we have always understood and appreciated the unique contribution twins can make to research – and now this message looks set to become more widely appreciated through the NASA twin study. The space project is a multi-faceted national cooperation between universities, corporations and government and aims to provide insights into the changes that may occur in spaceflight, using Mark, the earth residing twin, as the control.

While the outcomes of this research will assist NASA with managing the health of their astronauts during space missions, they will also be relevant to people living on earth.

For example, a big problem for astronauts relates to changes in the optic nerve that damage their vision. Through studying a twin pair in which one is in space and the other on earth, researchers will be able to discover the environmental effects that damage the optic nerve.

Closer to home, renowned eye researchers Professors David Mackey (Director of the Lions Eye Institute in WA) and Chris Hammond (Chair of Ophthalmology, King’s College in London) have been studying the genetics of glaucoma, optic atrophy and congenital cataracts for two decades. They believe that the research being conducted by NASA will help unravel some of the mysteries of why we develop eye disease. This is aligned with their own research project, The Twins Eye Study, the largest twin eye research data to date.

Prof Mackey asserts that “twin siblings provide an excellent natural experiment in which to investigate important genetic traits. Over the last 15 years we have examined the eyes of over 1000 sets of Australian twins (plus 19 triplets and 196 siblings). We now know much more about which aspects of the eye are determined by genetic factors such as the size and structure of the optic nerve. The optic nerve is damaged in the eye disease glaucoma and we have found that genes that affect the structure of the nerve also influence glaucoma risk and, we suspect the risk of damage to the optic nerve in space. It will be exciting to follow this ultimate experiment of having twins live in different environments and whether we can help in improving the safety of space travel”.

Photo: image credit – NASA Robert Markowitz