Radiation: rat sperm remains stable after 6 years in space


Radiation: Possible great news for future space travelers: Scientists have performed the longest biological experiment ever done on the International Space Station (ISS) and the results, published June 11, suggest that exposure to space radiation for long periods does not affect the DNA that will be passed on to future generations – at least in mice.

There are fears that chronic exposure to space radiation could not only put astronauts at risk for developing cancer and other diseases, but also for creating mutations in their DNA. These changes in genes, in theory, could be passed on to future generations. But the new results obtained from this study suggest that deep space travelers can have children safely, from a biological point of view, when they return from their missions.

How the experiment was done

For scientist Teruhiko Wakayama, from Yamanashi University in Kofu, Japan, and his colleagues, studying how space radiation affects reproduction was a complicated challenge: it would not be possible to accurately mimic space radiation with the equipment available here on Earth and the International Space Station did not have freezers for long-term storage of cells.

The solution found by the team was to lyophilize – to dehydrate by sublimation – the mice’s sperm and only then send it to space. With the process, it became possible to store the substance at room temperature.

For the study, the team selected the 12 best males among 66 mice, taking into account the quality of the ampoules. The 24 best vials of each male were selected and then divided into six boxes. Three were sent into space and preserved in ISS, while another three boxes were preserved here on Earth.