In this article, we address misunderstandings about genetic essentialism, genetic determinism, and genetic reductionism. There are good reasons to carefully consider the meanings and relationships that characterize genetic essentialism, genetic determinism, and genetic reductionism; these are different (if related) concepts, despite their superficial resemblances. Although a recent Nature Reviews Genetics article addressed these issues, problems intrinsic to them remained unexplored, problems that we address here by adopting a developmental systems perspective. Discussions of these concepts should explicitly communicate that genetic essentialism fails because individuals are as they are in part due to the contexts in which they develop, that genetic determinism fails because all phenotypes depend on co-acting genomic and non-genomic factors for their development, and that genetic reductionism fails because emergent properties above the level of the genome can feed back and influence the subsequent functioning of that genome. Elucidating the meaning of these concepts without providing arguments for rejecting them is problematic. Developmental science offers the required arguments.