Freeze-dried mouse sperm nucleus has tolerance against extreme environments

To demonstrate the tolerance of mammalian sperm nucleus against extreme environments, mouse spermatozoa were freeze-dried and treated with 95 °C for 1 h or irradiated at over 5 Gy. Although all sperm were ostensibly dead after rehydration, healthy offspring were obtained from recovered sperm nuclei. The normality of those offspring were examined by microarray, and no difference were detected compare to fresh control offspring. Neonate brain derived from fresh spermatozoa, freeze-dried (FD) spermatozoa, 5 Gy X-ray irradiated FD spermatozoa and FD spermatozoa treated at 95 °C for 1 h were used.