A new breed of "space pups" are gaining the attention of the scientific world. This was after mice sperm stored inside the International Space Station (ISS) produces healthy offspring.

This proves that extended stay aboard the ISS does not affect sperm fertility, at least for the mice sperm samples. The mice sperm were used in order to complete a study. The fertilized mice sperm was frozen dried and was stored inside the ISS for one year.

The space pups pave the way for future reproduction of animals and potentially humans beyond the comforts of the Earth. Despite having proven that mice sperm can survive long storage period in space, researchers say that it will need more research in order to fully grasp how space can influence reproduction.

The study was published in the journal PNAS. The point of the study is to find out whether extensive stay in space can damage the DNA. People spending time aboard the ISS receives about 10 to 100 times more exposure to radiation. This subjects all systems in their bodies including the reproductive organs to radiation as well.

Based on the study, the sperm, which spent about 288 days in space between 2013 and 2014, show some damage to their DNA. However, this did not affect the sperm from producing offspring. They were still able to fertilize eggs when brought back to Earth. Despite some known changes in the DNA, researchers say that the difference between mice sperm stored in space and the ones kept on the planet is very little.

"We got many healthy offspring from space sperm," Teruhiko Wakayama, a biologist at the University of Yamanashi in Japan and lead author of the study, said in an interview with The Verge. "Those pups could not have any genetic damage."

The topic is highly controversial and vital if mankind is keen on establishing colonizations beyond Earth, like Mars. Radiation remains to be a key concern when it comes to reproduction in space. Will this work on human sperm, too?

"In the future, humans likely will live on large-scale space stations or in other space habitats for several years or even over many generations," the researchers said in the paper. "If humans ever start to live permanently in space, assisted reproductive technology using preserved spermatozoa will be important for producing offspring."

Although it's still too early to tell if this method will work for human sperm cells, experts are positive that the result will lead to further discoveries. They also have to find more technologies to save the human race and the reproduction system from being exposed to radiation in space.