Knockout of Rlim Results in a Sex Ratio Shift toward Males but Superovulation Cannot Compensate for the Reduced Litter Size

Abstract

Technologies that can preselect offspring gender hold great promise for improving farm animal productivity and preventing human sex-related hereditary diseases. The maternal Rlim allele is required for imprinted X-chromosome inactivation, which is essential for the normal development of female mouse embryos. In this study, we inactivated the maternal Rlim allele in embryos by crossing a male transgenic mouse line carrying an X-linked CMV-Cre transgene with a female line carrying a loxP-flanked Rlim gene. Knockout of the maternal Rlim gene in embryos resulted in a male-biased sex ratio skew in the offspring. However, it also reduced litter size, and this effect was not compensated for by superovulation in the mother mice. In addition, we showed that siRNA-mediated knockdown of Rlim in mouse embryos leads to the birth of male-only progenies. This study provides a new promising method for male-biased sex selection, which may help to improve the productivity in livestock and prevent sex-associated hereditary diseases in humans.

RNA-Seq study of in vivo-produced single male and female bovine blastocysts

“…Secondly, it can enhance the intensity of good traits, speed up the breeding process, and reduce the breeding cost, resulting in maximum genetic progress. In addition, the phenomenon of twin infertility can be overcome by controlling the sex of offspring, and the harm of sex-related harmful genes can be eliminated (Peng et al, 2023). At present, sex control technology is gradually improving, and many existing problems have been solved.…”