Restoration of the Normal Splicing Pattern of the PLP1 Gene by Means of an Antisense Oligonucleotide Directed against an Exonic Mutation

An exonic missense mutation, c.436C>G, in the PLP1 gene of a patient affected by the hypomyelinating leukodystrophy, Pelizaeus-Merzbacher disease, has previously been found to be responsible for the alteration of the canonical alternative splicing profile of the PLP1 gene leading to the loss of the longer PLP isoform. Here we show that the presence of the c.436C>G mutation served to introduce regulatory motifs that appear to be responsible for the perturbed splicing pattern that led to loss of the major PLP transcript. With the aim of disrupting the interaction between the PLP1 splicing regulatory motifs and their cognate splicing factors, we designed an antisense oligonucleotide-based in vitro correction protocol that successfully restored PLP transcript production in oligodendrocyte precursor cells.