Effects of superovulation, in vitro fertilization, and oocyte in vitro maturation on imprinted gene Grb10 in mouse blastocysts.

Grb10 is a key imprinted gene that is suspected to have a role in the adverse outcomes of assisted reproductive technology (ART), but little is known about the effects of ART on it. Primary ART techniques, including superovulation, in vitro fertilization (IVF), and oocyte in vitro maturation (IVM), were analyzed in this study of the effects of ART on embryo quality and Grb10. Embryo development rates were determined. Blastocyst cell number and global methylation were analyzed at the single-embryo level, together with Grb10 methylation and mRNA expression of the imprinted genes. Lower blastocyst cell number, higher genome and Grb10 CGI1 methylation, and variable mRNA expression were observed in the ART groups compared with the control group. Whether fertilization was in vivo or in vitro, the changes in the genome and Grb10 CGI1 methylation level and Grb10 and H19 expression were similar in the groups with superovulation and more significant than the IVM group. These results suggest that superovulation had a greater impact than IVF or IVM on the genome and Grb10 DNA methylation level, and Grb10 and H19 expression.