In particular, the robust finding here, of depleted levels of UBA1 in iPSC-derived motor neurons from three separate SMA patients compared to controls, supports a growing body of evidence (Ramser et al., 2008; Dlamini et al., 2013; Wishart et al., 2014)to suggest that this protein is likely to be a major contributor to pathogenesis in SMA. The gene discussed is UBA1; the disease is proximal spinal muscular atrophy.