SMN1 and proximal spinal muscular atrophy: Hence, cells with low amounts of SMN, including those derived from SMA patients, were found to have reduced protein levels of select Gemins (Jablonka et al., 2002; Helmken et al., 2003; Feng et al., 2005; Shpargel and Matera, 2005; Carissimi et al., 2006; Gabanella et al., 2007; Hao le et al., 2007).