Genes are generally regarded as the essence of a living being that determines all its characteristic properties. However this notion no longer applies from a biological perspective.Central to this book therefore is the question of why and how essentialist thinking influences the social perception of biological research projects to this day. Based on current genetics and epigenetics knowledge, Kirsten Schmidt goes looking for a new interpretation of the concept »gene« in the post-genomics era. The understanding of genes as dynamic processes proves to be a fruitful alternative to essentialism.