Tags

Type your tag names separated by a space and hit enter

Becker muscular dystrophy caused by an intronic mutation reducing the efficiency of the splice donor site of intron 26 of the dystrophin gene.
Neuromuscul Disord. 2009 Mar; 19(3):189-92.ND

Abstract

We describe an 11-year-old boy with dystrophinopathy who presented with a history of progressive proximal muscle weakness and elevated serum creatine kinase levels at age 6. Sequence analysis of the dystrophin (DMD) gene did not identify a mutation in the coding regions but revealed a nucleotide substitution in intron 26 (c.3603+3A>T). Since computer algorithms did not conclusively indicate that this sequence variant inactivated the splice site, we analyzed the DMD mRNA from a muscle biopsy of the patient to determine its functional significance. PCR and sequence analysis of the cDNA demonstrated that the mutation reduced the efficiency of the donor splice site and caused activation of a cryptic donor site 113 bp downstream. Activation of the cryptic donor site led to inclusion of 116 bp of intronic sequence containing a stop codon producing a truncated dystrophin protein. Residual wild-type splicing was also detected, which would explain the milder Becker rather than Duchenne phenotype in this patient. We highlight the importance of mRNA analysis for determination of pathogenicity in patients with ambiguous sequence variants in the DMD gene.

Authors+Show Affiliations

Division of Molecular Genetics, Department of Paediatric Laboratory Medicine, The Hospital for Sick Children, 555 University Avenue, Toronto, Ont., Canada. berivan.baskin@sickkids.caNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

19230662

Citation

Baskin, Berivan, et al. "Becker Muscular Dystrophy Caused By an Intronic Mutation Reducing the Efficiency of the Splice Donor Site of Intron 26 of the Dystrophin Gene." Neuromuscular Disorders : NMD, vol. 19, no. 3, 2009, pp. 189-92.
Baskin B, Banwell B, Khater RA, et al. Becker muscular dystrophy caused by an intronic mutation reducing the efficiency of the splice donor site of intron 26 of the dystrophin gene. Neuromuscul Disord. 2009;19(3):189-92.
Baskin, B., Banwell, B., Khater, R. A., Hawkins, C., & Ray, P. N. (2009). Becker muscular dystrophy caused by an intronic mutation reducing the efficiency of the splice donor site of intron 26 of the dystrophin gene. Neuromuscular Disorders : NMD, 19(3), 189-92. https://doi.org/10.1016/j.nmd.2008.11.003
Baskin B, et al. Becker Muscular Dystrophy Caused By an Intronic Mutation Reducing the Efficiency of the Splice Donor Site of Intron 26 of the Dystrophin Gene. Neuromuscul Disord. 2009;19(3):189-92. PubMed PMID: 19230662.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Becker muscular dystrophy caused by an intronic mutation reducing the efficiency of the splice donor site of intron 26 of the dystrophin gene. AU - Baskin,Berivan, AU - Banwell,Brenda, AU - Khater,Reem Al, AU - Hawkins,Cynthia, AU - Ray,Peter N, Y1 - 2009/02/18/ PY - 2008/08/15/received PY - 2008/10/21/revised PY - 2008/11/03/accepted PY - 2009/2/24/entrez PY - 2009/2/24/pubmed PY - 2009/7/29/medline SP - 189 EP - 92 JF - Neuromuscular disorders : NMD JO - Neuromuscul Disord VL - 19 IS - 3 N2 - We describe an 11-year-old boy with dystrophinopathy who presented with a history of progressive proximal muscle weakness and elevated serum creatine kinase levels at age 6. Sequence analysis of the dystrophin (DMD) gene did not identify a mutation in the coding regions but revealed a nucleotide substitution in intron 26 (c.3603+3A>T). Since computer algorithms did not conclusively indicate that this sequence variant inactivated the splice site, we analyzed the DMD mRNA from a muscle biopsy of the patient to determine its functional significance. PCR and sequence analysis of the cDNA demonstrated that the mutation reduced the efficiency of the donor splice site and caused activation of a cryptic donor site 113 bp downstream. Activation of the cryptic donor site led to inclusion of 116 bp of intronic sequence containing a stop codon producing a truncated dystrophin protein. Residual wild-type splicing was also detected, which would explain the milder Becker rather than Duchenne phenotype in this patient. We highlight the importance of mRNA analysis for determination of pathogenicity in patients with ambiguous sequence variants in the DMD gene. SN - 1873-2364 UR - https://www.unboundmedicine.com/medline/citation/19230662/Becker_muscular_dystrophy_caused_by_an_intronic_mutation_reducing_the_efficiency_of_the_splice_donor_site_of_intron_26_of_the_dystrophin_gene_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0960-8966(08)00682-2 DB - PRIME DP - Unbound Medicine ER -