There has been an enormous progress in understanding of how genes contribute to both normal and abnormal development. Also many laboratory works are exploring the intricacies of how to develop in the human central nervous system. Understanding the mechanisms of cortical development gives essential insight into the pathogenesis of many genetic and acqured developmental psychiatric disorders, including autism, schizophrenia, and teaming disorder. Genes have been implicated in an ever-increasing number of disorders. Advance in genetics have begun to clarify the molecular basis of not only single-gene disorders, but also more complex phenotypes.