Pseudoexon exclusion by antisense therapy in methylmalonic aciduria (MMAuria).
Development of pseudoexon exclusion therapies by antisense modification of pre-mRNA splicing represents a type of personalized genetic medicine. Here we present the cellular antisense therapy and the cell-based splicing assays to investigate the effect of two novel deep intronic changes c.1957-898A>G and c.1957-920C>A identified in the methylmalonyl-coenzyme A (CoA) mutase (MUT) gene. The results show that the nucleotide change c.1957-898A>G is a pathological mutation activating pseudoexon insertion and that antisense morpholino oligonucleotide (AMO) treatment in patient fibroblasts leads to recovery of MUT activity to levels 25 to 100% of control range. On the contrary, the change c.1957-920C>A, identified in two fibroblasts cell lines in cis with c.1885A>G (p.R629G) or c.458T>A (p.D153V), appears to be a rare variant of uncertain clinical significance. The functional analysis of c.1885A>G and c.458T>A indicate that they are the disease-causing mutations in these two patients. The results presented here highlight the necessity of scanning the described intronic region for mutations in MUT-affected patients, followed by functional analyses to demonstrate the pathogenicity of the identified changes, and extend previous work of the applicability of the antisense approach in methylmalonic aciduria (MMAuria) for a novel intronic mutation.
Centro de Diagnóstico de Enfermedades Moleculares, Centro de Biología Molecular Severo Ochoa Universidad Autónoma de Madrid (UAM)-Consejo Superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid, Madrid, Spain.
B
B
Pérez
A
A
Rincón
A
A
Jorge-Finnigan
E
E
Richard
B
B
Merinero
M
M
Ugarte
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LR
Desviat
D001483:Base Sequence; D002460:Cell Line; D005091:Exons / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007438:Introns / Q000235:genetics; D008661:Metabolism, Inborn Errors / Q000188:drug therapy* / Q000201:enzymology; D008765:Methylmalonyl-CoA Mutase / Q000172:deficiency; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D016376:Oligonucleotides, Antisense / Q000627:therapeutic use*; D010641:Phenotype; D011422:Propionates / Q000378:metabolism; D012326:RNA Splicing / Q000235:genetics
D016376:Oligonucleotides, Antisense; D011422:Propionates; D008765:Methylmalonyl-CoA Mutase; C029658:propionic acid