Change of epigenetic modification and human reproduction

In recent years, it has become consumedly clear that changing of epigenetic modification is essential during both early and late oogenesis and spermatogenesis. Also epigenetic modifications are involved in some cases such as embryo development and growth, diseases and responsible for X-chromosome inactivation and genomic imprinting. Epigenetic reprogramming can be explained as any mitotic or meiotic changing which does not result any alteration in DNA sequence but will have important effect on the normal embryonic development. Germline epigenetic reprogramming in addition to requiring epigenetic modification to compose the germline, the primordial germ cells uniquely undergo striking wave of epigenetic reprogramming that most other lineage do not undergo. Epigenetic modification is affected by both internal factors and environmental factors during pre- and post-natal development. Because all of the epigenetic modification steps are not clear, by means of understanding epigenetic modification, misreprogramming of these steps can be modified with the aid of drugs and nutrients. Moreover, epigenetic regulation is essential to obtain the biological intricacy of multicellular organisms, cloning and producing of offspring by assisted reproductive technology (ART).The objective of this review is to provide comprehensive summary of the current knowledge in the field of epigenetic modification in relation to male and female germline development and reproduction.