In this episode, Xavier Bonilla has a dialogue with Kevin Mitchell on genetics, neuroscience, and variation in development. They discuss why developmental variation is important to understanding genes and environment through the trajectory of the lifespan. They talk about how a person responds to the environment and why this is a key essential feature for gene and environment interaction. They talk about the genome as a system or program that can interact with other "noise" in the system. They make the distinctions between traits and genes and how neuropsychiatric disorders are implicated by genetic variation. The provide an example of heritability using Autism and the various genes involved in the development of Autism. They talk about how much genetic programming is set before birth and also provide a definition of environment. They use intelligence as an example to explain the differences in the nature vs. nurture debate. They talk about the importance of twin studies, use of polygenic scores, epigenetics, neuroplasticity, and many other topics. Kevin Mitchell is an Associate Professor of Genetics and Neuroscience at Trinity College Dublin. He has his BA in Genetics from Trinity College Dublin and his PhD in Neurobiology from the University of California at Berkeley. His current research focuses on genetics and wiring of the brain specifically as it relates to neuropsychiatric disorders. He is the author of Innate: How the wiring of our brains shapes who we are which you can purchase here. He also has his own blog. Twitter: @wiringthebrain