Spinal muscular atrophy (SMA) is a neurogenetic disorder caused by a loss or mutation in the survival motor neuron 1 gene (SMN1) on chromosome 5q13, which leads to reduced SMN protein levels and a selective dysfunction of motor neurons. SMA is an autosomal recessive, early childhood disease with an incidence of 1:10,000 live births. SMA is the leading cause of infant mortality due to genetic diseases. The purpose of this registry is to assess the long term outcomes of patients with SMA in the context of advances in treatment options and also to characterize and assess long-term safety and effectiveness of OAV-101.