Making Babies in Space May Be Harder Than It Sounds
By Brandon Keim   August 25, 2009  |  1:44 pm  |  Categories: Biology, Space


Experimental mouse breeding in a near-zero-gravity space simulation suggests 
making babies is best left to Earthlings.



According to Japanese biologists, defects in their microgravity embryos suggest 
that "fertilization can occur normally" in space, but standard Earth gravity 
may be needed for embryo development.

The experiment, published Tuesday in Public Library of Science ONE, is the 
latest addition to a surprisingly large body of literature on how the space 
environment affects the cellular basics of reproduction.

Among the animals that have been bred in space are frogs, salamanders, sea 
urchins — who didn't do so well — and fish. (Birds and bees are, understandably 
if unfortunately, not on the list.)

Rather less research, however, has been done on mammalian reproduction in 
space, and there's reason to think the potential effects of low gravity would 
be pronounced in mammals, whose embryonic development is more complicated and 
sensitive than other animals.

To test these effects, the researchers artificially fertilized mouse eggs with 
sperm that had been stored inside a three-dimensional clinostat, a machine that 
mimics weightlessness by rotating objects in such a way that the effects of 
gravity are spread in every direction.

Fertilization took place normally, suggesting that microgravity hadn't harmed 
the sperm. But as the embryos continued to develop inside the clinostat, many 
developed problems. Their cells had trouble dividing and maturing.

Some were ultimately implanted in female mice and survived to a healthy birth, 
but at lower numbers than a regular-gravity control group. Part of the 
difference could be the result of performing tricky procedures on sensitive 
cells, but the researchers suspect they also reflect the affect of a 
low-gravity environment on cellular processes that evolved for Earth-specific 
physics.

"Sustaining life beyond Earth either on space stations or on other planets will 
require a clear understanding of how the space environment affects key phases 
of mammalian reproduction," write the researchers.

Citation: "Detrimental Effects of Microgravity on Mouse Preimplantation 
Development In Vitro." By Sayaka Wakayama, Yumi Kawahara, Chong Li, Kazuo 
Yamagata, Louis Yuge, Teruhiko Wakayama. Public Library of Science ONE, August 
25, 2009.

Images: PLoS ONE
http://www.wired.com/wiredscience/2009/08/spacebabies/

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