SMN1 and proximal spinal muscular atrophy: In our study, to better represent the level of SMN depletion in the liver observed in SMA and elucidate the intricate interplay between SMN deficiency in the liver and its systemic impact in SMA-like pathology, we utilized a mouse model employing Alb-Cre, where the albumin promoter drives expression of Cre recombinase in a liver-specific manner.