Gene expression as a tool for quality assessment of bovine oocytes and embryos

Suboptimal conditions of oocyte maturation and embryo culture in vitro reduce their developmental competence as compared to in vivo development. It is well known now that some IVF blastocysts, despite a proper morphology, are not able to hatch and implant after transfer. Therefore, it is suggested that during in vitro culture embryos show an ability to adjust to suboptimal conditions, which is however accompanied by changes in gene expression pattern resulting in reduced quality. Although gene expression analysis, as an invasive method, is considered as an indirect way of embryo quality evaluation, it provides valuable data on the processes crucial for growth and development.