Effect of vitrification on development and imprinted gene in mouse embryos.

Vitrification of embryos is a routine procedure in IVF ( fertilization) laboratories. In the present study, we aimed to investigate the effect of vitrification on mouse preimplantation embryo development , and effect on the epigenetic status of imprinted gene in mouse embryos. The blastocyst formation rate for vitrified 8-cell embryos was similar to the non-vitrified 8-cell embryos, whereas the blastocyst hatching rate was lower than that of the non-vitrified group. The expression level of major-type transcript decreased significantly in vitrified blastocysts compared with non-vitrified and blastocysts. Moreover, the global DNA methylation level in 8-cell embryos and blastocysts, and the DNA methylation at CpG island 1 (CGI1) of in blastocysts were also significantly decreased after vitrification. culture condition had no adverse effect, except for on the DNA methylation in CGI1. These results suggest that vitrification may reduce the development of mouse 8-cell embryos and affect the expression and DNA methylation of imprinted gene .