are highly invasive, ethically problematic to obtain and yield little material. Moreover, post-mitotic neurons cannot be expanded in vitro. Commonly used cell lines do not apply to the study of neuropsychatric diseases, and only a few immortalized brain-derived cell lines exist. Furthermore, the few relevant cell lines fail to fully recapitulate disease etiology or patient genetics. Currently, the best method of accessing patient-specific brain tissues is post-mortem sampling, which typically represents late stages of disease and offers little direct insight into the pathogenesis of disorders that often present early in life. In addition, these tissues rarely represent the natural course of disease progression because most patients receive some form of medical or psychological intervention after diagnosis. Layered on these confounding factors are the various comorbidities that accompany mental illness and variations in artifacts owing to different methods of fixation and storage of post-mortem tissues. Thus, advancing our understanding of neuropsychiatric disease will rely on technology that allows greater access to human neuronal cell types affected in mental illness and is capable of capturing patient genetic makeup. Such an advance would facilitate the study of neuropsychiatric disorders at a cellular and molecular level and the role of genetic variants in disease
