• epigenetic;
  • embryo;
  • DNA remodeling;
  • preimplantation development

Within the past few years, developmental scientists have switched their attention from the study of DNA sequencing to the epigenetic state of the genome. Studying epigenetics could present the key to understanding gene expression changes without altering the basic structure of DNA. For example, the blastocyst, trophectoderm, and inner cell mass grow within the same environment, having the same genome, but differentiate differently. Each stage of embryo development is characterized by a specific epigenetic pattern. These modifications give the embryos the ability to interact with the uterus. Gene expression profiles change dramatically, and chromatin remodeling allows for core histone elements to undergo significant modifications. In the past, epigenetic mechanisms were studied using less accurate technologies such as PCR techniques and gel electrophoresis. Today microarray, DNA analyzers, and other in silico approaches give us the capability to understand the epigenetic impact on differentiation and cell fate.