TITLE: Directed Evolution of Novel AAV Capsids for Global CNS Delivery in Rodents and Primates ABSTRACT Many monogenic based neurological disorders present attractive targets for gene therapy, but even with promising proof-of-concept rodent studies, successful clinical translation depends upon efficient transgene delivery and expression across the entire central nervous system (CNS). Directed evolution is a powerful and proven method to develop novel adeno-associated virus (AAV) vector capsids that exhibit properties distinct from naturally occurring serotypes. However, to date, the majority of novel capsids have been derived in rodents or in vitro models whose properties may or may not translate to other species, in particular primates. This proposal will utilize AAV capsid DNA shuffling directed evolution to develop gene delivery vectors for a number of human CNS disease applications. To do this, parallel selections and recovered clone characterization will be carried out in mice and non-human primates (NHPs), combining the expertise of experts on both CNS gene transfer in NHPs and AAV vector design. The experimental plan should independently generate superior AAV capsids capable of global CNS delivery, with cross-compatibility between mice and NHPs. Moreover, we have designed our experimental approach to generate vectors that exhibit selective tropism for neurons, astrocytes, and/or oligodendrocytes, which would be invaluable reagents for research and therapeutic applications. If successful, the AAV capsid reagents generated should create new research tools, broaden the application of gene therapy to more CNS disorders, and facilitate the translation of existing CNS gene therapy approaches to humans.