Table S1.

Lengths of comet tails in ground and space-preserved spermatozoa

Mouse strainCondition of preservation*No. of spermatozoaAverage length of comet tailSDP value, Wilcoxon–Mann–Whitney test
C57BL/6Ground931.000.16
Space931.0020.28>0.2
BDF1Ground3921.000.20
Space3921.280.21<0.001
BCF1Ground2381.000.23
Space2381.030.25<0.001
129B6F1-GFPGround1111.000.32
Space1111.480.39<0.001
  • * 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.

  • To standardize the results between different mouse strains, the lengths of each DNA comet tail were divided by the mean length of the ground control results in each strain.