Figure 2

Chemistries used for the exon skipping approach. Artificially developed AO such as peptide nucleic acid (PNA), 2'O-Methyl-phosphorothiate-antisense oligonucleotides (2'OMeAO), phosphorodiamidate morpholino oligomer (PMO) and peptide conjugated PMO (PPMO) are shown for comparison with DNA and RNA. PNA's backbone is composed of repeating N-(2-aminoethyl)-glycine units linked by peptide bonds, PMO have a morpholine ring instead of the deoxyribose ring in DNA or ribose ring in RNA and 2'OMeAO are similar to RNA but methylated at the 2'-OH position of the ribose ring.