CI is interpreted to involve a modification-rescue system [6]: Wolbachia in infected males modify the sperm, and the same strain of Wolbachia must be present in the egg to rescue the modification, or the embryo will typically fail to complete development.
In conclusion, the 6.6 dietary ratio and 400 mg/kg vitamin E supplementation improve progressive sperm motility by modifying the sperm FA composition and antioxidant status.
To persist, PSR is thought to modify the hereditary material of the developing sperm, with the result that all nuclear DNA other than the PSR chromosome is destroyed shortly after fertilization.
Many animals modify the number or quality of sperm in response to increased sperm competition [8] [12].
"The question is whether the sperm is as good" as the sperm of normal males.
The sperm of men with impaired sperm morphology was characterized by a higher proportion of sperm head vacuoles.
Some maternally inherited parasites bias host progeny sex ratios in favour of female offspring, through which they then achieve transmission (by feminization, parthenogenesis induction or male-killing); others modify sperm of infected males, in order to reduce the fitness of the uninfected females with which they mate (cytoplasmic incompatibility) [ 2].
Genetic research has lately progressed so far that, this year, a group of scientists and practitioners gathered in Napa, California, to urge a ban on modifying the genetic material of human sperm, eggs, and embryos, a process known as germline editing.
Substantiating a previous suggestion by Imamura et al. [17], our results suggest that non-CpG methylation depends on the prior establishment of a CpG methylation pattern, the only feature that seems to be common to all the sperm nuclei of modified males.
