Title:Genes and Conditions Controlling Mammalian Pre- and Post-implantation Embryo Development
Volume: 16
Issue: 1
Author(s): G. Anifandis, C.I. Messini, K. Dafopoulos and I.E. Messinis
Affiliation:
Keywords:
Assisted reproduction, DNA methylation, Human embryology, Imprinting errors.
Abstract: Embryo quality during the in vitro developmental period is of great clinical importance. Experimental
genetic studies during this period have demonstrated the association between specific gene expression
profiles and the production of healthy blastocysts. Although the quality of the oocyte may play a major role
in embryo development, it has been well established that the post – fertilization period also has an important
and crucial role in the determination of blastocyst quality. A variety of genes (such as OCT, SOX2,
NANOG) and their related signaling pathways as well as transcription molecules (such as TGF-β, BMP)
have been implicated in the pre- and post-implantation period. Furthermore, DNA methylation has been lately characterized
as an epigenetic mark since it is one of the most important processes involved in the maintenance of genome stability.
Physiological embryo development appears to depend upon the correct DNA methylation pattern. Due to the fact that
soon after fertilization the zygote undergoes several morphogenetic and developmental events including activation of embryonic
genome through the transition of the maternal genome, a diverse gene expression pattern may lead to clinically
important conditions, such as apoptosis or the production of a chromosomically abnormal embryo. The present review focused
on genes and their role during pre-implantation embryo development, giving emphasis on the various parameters
that may alter gene expression or DNA methylation patterns. The pre-implantation embryos derived from in vitro culture
systems (in vitro fertilization) and the possible effects on gene expression after the prolonged culture conditions are also
discussed.
