Table S2.

Brightness of male pronuclei fertilized with ground or space-preserved spermatozoa and immunostained with anti–gamma-H2AX antibody

Mouse strainCondition of preservation*No. of zygotesAverage brightness of male pronucleusSDP value, t test
C57BL/6Ground211.1230.101
Space181.1700.096>0.1
BDF1Ground231.1470.108
Space241.1650.117>0.1
BCF1Ground221.1490.095
Space221.2530.178<0.05
129B6F1-GFPGround211.1500.146
Space191.2100.095>0.1
  • * Ground: At the same times and for the same durations as when launching and storing the sample case, a control sample case was exposed to room temperature, then frozen at –95 °C and stored in a freezer at the Tsukuba Space Center in Japan. These are referred to as ground control sperm samples. Space: Samples were launched and stored on the ISS for 9 mo.

  • The brightness of the whole male pronucleus was assayed using ImageJ, and then subtracted from the brightness of the zygote cytoplasm.