Environmental factors and gene-environment interactions

This chapter provides a concise outline of selected nongenetic risk factors associated with two neurodevelopmental disorders - schizophrenia and autism. It also outlines how clues from genetics and epidemiology can be combined with respect to the disorders of interest. There are important opportunities ahead where both epidemiology and genetics can converge to catalyze discovery in the field of neurodevelopmental disorders. The chapter focuses on exposures during the prenatal and early life period. However, there is consistent evidence that (a) cannabis uses, and (b) exposure to trauma, are associated with an increased risk of psychosis. Epidemiology has a particular focus on modifiable risk factors, and some modifiable variables are well suited to public health intervention (e.g., nutrition and infection). Public health has long recognized the value of nonspecificity of outcomes. It facilitates more "intellectual collisions" between the fields of genetics and epidemiology