Fig. 2.

Potential therapeutic approaches for spinal muscular atrophy (SMA). (A) Compounds that have been or will be tested in clinical studies. (B) Gene therapy can be achieved by delivering full length SMN1 cDNA into patients with SMA; (C) Trans-splicing can be used to correct exon 7 skipping in the SMN2 gene; (D) A bifunctional oligonucleotide can recruit splicing factors to exon 7, leading to more exon 7 inclusion in SMN2 mRNA; (E) Anti-sense oligonucleotides would block negative elements in SMN splicing, stimulating exon 7 inclusion into SMN2 mRNA.