Can oocytes repair fragmented DNA of spermatozoa?

DNA repair by oocytes.

Experimental evidence in a number of different in vivo and in vitro systems indicates clearly that the vertebrate oocyte is capable of repairing endogenous and exogenous DNA damaged as a result of meiotic recombination, the action of UV and X-irradiation or the effects of mutagenic chemicals. It would appear that both before and after the dictyate stage of meiosis the oocyte has less repair cap...

Investigation of DNA repair in human oocytes and preimplantation embryos

Selection against spermatozoa with fragmented DNA after postovulatory mating depends on the type of damage

BACKGROUND Before ovulation, sperm-oviduct interaction mechanisms may act as checkpoint for the selection of fertilizing spermatozoa in mammals. Postovulatory mating does not allow the sperm to attach to the oviduct, and spermatozoa may only undergo some selection processes during the transport through the female reproductive tract and/or during the zona pellucida (ZP) binding/penetration. ME...

Microdroplet In Vitro Fertilization Can Reduce the Number of Spermatozoa Necessary for Fertilizing Oocytes

Successful in vitro fertilization (IVF) in mice has been achieved using spermatozoa at concentrations specifically optimized for the experimental conditions, such as species and source of spermatozoa. Although IVF in mice is mostly performed using about 80-500 µl drops, it is expected that the number of spermatozoa used for insemination can be reduced by decreasing the size of the IVF drops. Th...

Mouse oocytes injected with testicular spermatozoa or round spermatids can develop into normal offspring.

Genomic imprinting occurs in both male and female gametes during gametogenesis, but the exact time when imprinting begins and ends is unknown. In the present study we injected nuclei of testicular spermatozoa and round spermatids into mature mouse oocytes to see whether these nuclei are able to participate in syngamy and normal embryonic development. If the injected oocytes develop into normal ...