Human molecular genetics
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Human molecular genetics · Jul 1998
Modification of splicing in the dystrophin gene in cultured Mdx muscle cells by antisense oligoribonucleotides.
Deletions and point mutations in the gene encoding the cytoskeletal protein dystrophin and its isoforms cause either the severe progressive myopathy Duchenne muscular dystrophy (DMD) or the milder Becker muscular dystrophy (BMD), largely depending on whether the reading frame is lost or maintained respectively. Frameshift mutations tend to result in a lack of dystrophin at the sarcolemma, destabilization of the membrane and degeneration of skeletal muscle. The mdx mouse is a valuable animal model of DMD as it bears a nonsense point mutation in exon 23 of the murine DMD gene leading to an absence of dystrophin expression in the muscle sarcolemma and muscular dystrophy. ⋯ Dystrophin expression was observed in the sarcolemma of transfected mdx myotubes after transfection by an oligonucleotide complementary to the 3' splice site of murine dystrophin intron 22. Direct sequencing of RT-PCR products from these cells revealed precise splicing of exon 22 to exon 30, skipping the mutant exon and creating a novel in-frame dystrophin transcript. As patients with comparable in-frame internal deletions show relatively mild myopathic symptoms, this may in the future offer a therapeutic approach for DMD, as well as for other inherited disorders.