Third, the ability to summarize aggregate genetic risk in a meaningful way opens up more opportunities for developmental psychologists and neuroscientists to use the theories and tools of their fields to more carefully delineate the mechanisms of risk going from genes to brain to behavior, and in conjunction with the environment. The falling cost of genome-wide genotyping arrays that cover both common and rare genetic variation (currently <100 USD) means that it is now financially feasible to collect genotypic data on samples for which there are detailed longitudinal developmental data. This permits examination of important process-oriented questions about the biological and psychological mechanisms through which genetic risk has its effect on genotype (e.g., through deficits in social information processing or structural or functional brain differences; Crick and Dodge, 1994; Huebner et al., 2008). Although a precision medicine approach for psychiatric disorders has yet to be realized (Collins and Varmus, 2015), identifying these mechanisms may provide critical insights about how to best implement prevention and intervention efforts so that the right people are intervened with at the right time.
