Genetics of brain networks and connectivity

The quest to identify genetic factors that affect the brain has several motivations. From a neuroscientific standpoint, there is a broad range of individual variation in all human traits including all aspects of behavior and cognition; population studies have shown these traits are partially influenced by variations in each individual's genetic code, among many other factors such as environmental hazards, toxins, trauma, nutrition, and education. With the advent of gene sequencing technology-and more recently the capacity to sequence an individual's genome-the scope of genetic studies has greatly advanced to include studies that try to pinpoint individual loci in the genome, or sets of such loci, where variations have a measurable impact on the human brain and behavior. At the same time, the whole field of genetics in animal models-from invertebrates to transgenic and outbred mice-has allowed, in some cases, direct manipulation of the genetic code to identify specific causal links between genetic variation, the brain, and behavior.