Spinal Muscular Atrophy (SMA) is a neurodegenerative disorder primarily affecting motor neurons, but immune dysfunction may contribute to disease progression and treatment response. While AAV9-delivered SMN1 gene therapy (e.g., Zolgensma) improves survival, long-term motor outcomes remain variable. This study integrates bulk and single-cell RNA sequencing (scRNA-seq) to define immune dysregulation in SMA. We analyzed peripheral blood from infants with SMA (n = 7 for bulk RNA-seq; n = 4 for...