The original neurodevelopmental hypothesis of schizophrenia presented by D.R. Weinberger in 1987 focused on pathogenesis and did not address etiology. Available evidence indicates that genetic factors are the principal cause of schizophrenia. It is imperative that any pathogenetic model for schizophrenia takes into account what is now known about genetic mechanisms of illness. Recent advances in molecular genetics can provide insights into the neurodevelopmental expression of the illness and what future genetic discoveries are likely to contribute to our understanding of schizophrenia. In this article, we propose a genetic model of etiopathogenesis that is consistent both with a modified neurodevelopmental hypothesis and our current knowledge about schizophrenia and molecular genetics.