Preimplantation stage-specific effect of culture environment on the DNA methylome of bovine blastocysts

The culture conditions of the early preimplantation embryos affects the DNA methylation landscape of the resulting blastocysts. Five groups of blastocysts were generated. The first (ZY), second (4C) and third (16C) blastocysts groups were obtained after transfer of in vitro developed zygote, 4-cell and 16-cell stage embryos, respectively to synchronized Simmental heifers followed by blastocysts recovery at day 7 of the estrous cycle. The fourth (IVP) and the fifth (VO) blastocyst groups represent those produced completely under in vitro and in vivo culture conditions, respectively. The global DNA methylation pattern of ZY, 4C, 16C and IVP blastocyst groups was investigated with reference to the VO group using EDMA array.