Abstract: It is disclosed herein that ssAAV and scAAV vectors of the same serotype administered by injection into the cerebrospinal fluid (CSF) via the intracerebroventricular (ICV) or intrathecal (cisternal or lumbar) route exhibit different cellular tropisms in the central nervous system. Thus, a subject can be treated by injection into the CSF of ssAAV or scAAV vector encoding a therapeutic protein, such as an ssAAV9 or scAAV9 vector. The therapeutic protein can be targeted to specific cells using these vectors. In some embodiments, scAAV9 is utilized to achieve superior transduction in the hippocampus, cerebellum and cerebral cortex where both neurons, particularly Purkinje neurons, and glial cells (such as astrocytes) are transduced. In other embodiments, ssAAV9 is utilized to minimize transduction of astrocytes. In further embodiments, an immunosuppressive agent is also administered to the subject.