This transgene consists of 3.4 kb promoter and 5'-untranslated region from the human SMN1 gene, the complete coding sequence of human SMN2 cDNA containing the silent C to T transition in exon 7 that results in the alternatively spliced transcript without exon 7 (SMNdelta7) and a TAG to TAT alteration in the first stop codon in exon 8 (change from a stop codon to a tyrosine), and the 3'-UTR of SMN1. The TAG to TAT change in exon 8 allows for translational stop codon read-through of the SMNdelta7 and generates an extended SMN2 protein. Thirteen lines were produced.