Freeze-dried mouse sperm stored on the International Space Station for nine months was successfully used to birth healthy mice offspring, a new study published in the Proceedings of the National Academy of Sciences shows.
The report reveals that animals and perhaps humans could potentially reproduce safely one day in space and a possible “doomsday vault” can be created to store sperm from endangered animals in outer space.
Japanese researchers sent samples of the preserved mice sperm to the ISS in August 2013. The sperm samples were preserved at minus 95 degrees Celsius (minus 135 degrees Fahrenheit) and exposed to cosmic radiation that was approximately 100 times more intense than on earth.
The scientists, from the University of Yamanashi, wanted to discover if prolonged exposure would affect or damage fertility and health of animal offspring.
The samples, which can be preserved at room temperature for up to two years, were returned by rocket to Japan in May 2014 and compared with other freeze-dried samples that were stored on earth, according to the study. The sperm was ultimately used to fertilize eggs which resulted in the successful birth of “space pups.” Although the space-preserved sperm received slightly more DNA damage, birthrates and female-to-male ratio were normal and the litter eventually reproduced offspring of their own.
“This was a little bit surprising, because the storage period was only nine months,” Study senior author Teruhiko Wakayama, a reproductive biologist at the University of Yamanashi in Kofu, Japan, told Space.com.
Wakayama suggests that if humans ever want to permanently live in outer space, they would have to bring animals that can effectively reproduce.
“If humans live in space for a very long time, then we will want to eat beefsteak,” he said.
The researchers claimed that overall, the outcome of the study suggests that the DNA damage was fixed after fertilization and healthy reproduction is certainly possible as a result of preserving animal sperm in outer space.
