About us Research we are funding Exon skipping with PNAs Action Duchenne also supported an exon-skipping project by Professor Haifang Yin in China with a three year project, which is shortly coming to an end entitled: “Developing Peptide Nucleic Acid Antisense Oligonucleotides for Duchenne Muscular Dystrophy.” Since 2006, Haifang Yin and Wood have started to investigate alternative antisense oligonucleotide (AO) chemistries, e.g. peptide nucleic acid (PNA). PNAs are DNA/RNA analogues formed by replacing the sugar phosphate backbone of the native nucleic acid with a synthetic glycine peptide backbone, which is stable and highly resistant to proteases and nucleases with high nucleic acid binding affinity and sequence specificity. The promising data from local and systemic PNA studies indicated that more systematic studies are warranted to fully characterize and explore the clinical potential of PNA AOs for Duchenne. After lots of trials and optimization, Haifang and the team proved the feasibility of synthesizing neutral and clinically applicable PNA AOs and establish the standard protocol, paving the way for developing PNA AOs to clinic. However, the scale-up needs to be further improved for a longer-term. While the team have been trying the best to establish the therapeutic PNA synthesis platform with a longer horizon to clinic, they have also been exploring other clinically applicable delivery approaches. The team are currently optimising novel formulations that can also facilitate the uptake of AOs in muscle.