Let's talk about the Halloween genes. Now you may be wondering, what are Halloween genes or more likely who lets scientists name things? I don’t know who gave scientists approval, but I know a little about the Halloween genes. The Halloween genes are a group of genes found in insects, primarily in flies that are responsible for the regulation and catalyzation of growth hormones. In flies, the most prominent branch of growth hormones is ecdysteroids, which is the fly equivalent of the human growth hormone. These ecdysteroids are essential for all stages of development, with research finding that specific Halloween genes are responsible for ecdysteroids in specific stages of development.