SMN1 and spinal muscular atrophy, type 1: Our results (Figure 1; Table 1) correlate with the published data, in which 73% of SMA type I patients carry two SMN2 copies, 78% of SMA II patients carry three copies, 49 and 44% of SMA III patients carry three and four copies, respectively, and 75% of SMA IV patients have four SMN2 copies (Calucho et al., 2018).