Mice whose sperm spent years in space are born

Japanese researchers found that mice sperm exposed for six years to high levels of radiation generated healthy “space hatchlings“according to a study published Friday in the academic journal Science Advances.

The sperm was saved lyophilized (dehydrated and frozen) in the International Space Station (ISS). Once on Earth he was rehydrated and spawned 168 offspring free of genetic defects.

Teruhiko Wakayama, a biologist and lead author of the study, told AFP that there are few differences between mice fertilized with sperm that were in space and those that were confined to our planet.

“All the pups looked normal,” he said, and when the genes were examined “no abnormalities found“.

In 2013, Wakayama and colleagues from the Japanese University of Yamanashi they sent to the ISS for his study three boxes, each of which contained 48 ampoules of lyophilized sperm.

The goal was to determine how long to radiation exposure from space could damage the DNA of reproductive cells or if mutations were generated, which could be a problem for our species in future exploration and space colonization missions.

What was sent to the ISS returned to Earth to fertilization in the first nine months, after two years, and finally after six and hundreds of births were generated.

The lyophilized sperm it was chosen for the experiment because it can be preserved at room temperature instead of needing a freezer.

The blisters were also very small and light, about the size of a small pencil, which reduced shipping costs.

When the “space mice“They reached adulthood, they mated randomly and the next generation also seemed normal.

Space colonies

Wakayama, who today directs the Center for Advanced Biotechnology of the Yamanashi UniversityHe told AFP that he was inspired by science fiction books by Heinlein and Asimov and once wanted to be an astronaut.

Although he became a scientist, he did not abandon his passion for the mysteries of space.

“In the future, when the time comes for migrate to other planets, we will need to maintain the diversity of genetic resources not only for humans but also for pets and domestic animals, “Wakayama and his colleagues said in the article.

“For cost and safety reasons, the stored cells are likely to be transported in spacecraft rather than live animals,” they add.

Reaching other planets means leaving the safety of Earth’s atmosphere and its magnetic field, which also extends for about 400 km above the ISS.

Deep space is full of strong radiation, both from solar particles and from cosmic rays that arrive from outside the solar system.

Eruptions on the solar surface generate particles that can have devastating impacts on human health and can penetrate the spacecraft of the current generation.

According to Wakayama, the freeze-drying process increases its tolerance compared to the fresh sperm, since the first does not have water within the cell nucleus and the cytoplasm.

According to the study authors, the elyophilized sperma it can be stored for up to 200 years in an orbital device.

Humanity may also want to spread its genetic resources off the planet in the event of a disaster on earth, adds the document.

The study cautions that there is still a need to investigate the effects of space radiation in female eggs and fertilized embryos before taking a new step in the space age.

DMZ