Meanwhile, although we observed significant differences in the percentages of SMN spot+ cells based on clinical subtype of SMA and the score of HFMS, we could not detect clear differences on the basis of the copy number of SMN2. Moreover, despite the most marked difference obtained being the comparison of the SMA subjects with the control subjects, no clear difference was detected in the MFI of SMN spot based on the HFMS score. This evidence concerns the gene SMN2 and proximal spinal muscular atrophy.