For example, injection in the intracerebroventricular (ICV) space of a self-complementary AAV serotype-9 vector expressing the codon-optimized human SMN1 coding sequence (coSMN1) resulted in the restoration of lifespan and growth with a mean lifespan of 346 days in SMA model mice in vivo [52]. Here, SMN1 is linked to proximal spinal muscular atrophy.