Opening the Door to Epigenetics in PCP

The term “epigenetics ” was coined in 1942 by the British developmental biologist Conrad H. Waddington and is derived from a combination of “epigenesis ” and “genetics”. Waddington defined the term of epigenetics as “the branch of biology that studies the causal interactions between genes and their products, which bring the phenotype into being” (Waddington 1942). He believed that the biological disciplines of development and genetics should be integrated, despite the fact that these fields were at the time considered to be totally distinct branches of biology. Waddington had the foresight to predict that fertilized zygotes developed into differentiated cells, tissues and individuals according to the information pro-vided by their genes, cell-cell communications, and also envir-onmental cues, by using the metaphorical illustration of an epigenetic landscape (Goldberg et al. 2007). Thus during th