Among the 103 potential SMA samples tested for copy number of SMN1 exon 7, the MLPA method detected 23 samples having 2 copies (normal), 1 sample having 3 copies (no SMA), 43 samples having 1 copy (SMA carrier) and 36 samples having 0 copies (SMA patient). Here, SMN1 is linked to proximal spinal muscular atrophy.