Neuropediatrics 2014; 45(05): 333-335
DOI: 10.1055/s-0034-1383824
Short Communication
Georg Thieme Verlag KG Stuttgart · New York

Xp21/A Translocation: A Rarely Considered Genetic Cause for Manifesting Carriers of Duchenne Muscular Dystrophy

Heike Trippe
1   Department of Neuropediatrics, Developmental Neurology and Social Pediatrics, University of Essen, Essen, Germany
,
Stefan Wieczorek
2   Department of Human Genetics, Ruhr-University Bochum, Bochum, Germany
,
Judith Kötting
2   Department of Human Genetics, Ruhr-University Bochum, Bochum, Germany
,
Wolfram Kress
3   Centre of Human Genetics, University of Würzburg, Würzburg, Germany
,
Ulrike Schara
1   Department of Neuropediatrics, Developmental Neurology and Social Pediatrics, University of Essen, Essen, Germany
› Author Affiliations
Further Information

Publication History

03 February 2014

14 May 2014

Publication Date:
21 July 2014 (online)

Abstract

Clinically manifesting carriers of Duchenne muscular dystrophy (DMD) are rare among the pediatric population. A standardized diagnostic procedure in supposed DMD carriers entails performing a Multiplex Ligation-dependent Probe Amplification analysis of the DMD gene first, then taking a muscle biopsy to confirm reduced dystrophin levels and/or finally a complete sequencing of the DMD gene. We describe a girl with high-elevated creatine kinase, myalgia, and cardiomyopathy. Muscle biopsy showed a dystrophic pattern and nearly absent expression of dystrophin. Diagnosis could not be confirmed by molecular genetic procedures. Because of a mild mental retardation, a chromosome analysis and molecular karyotyping were performed, revealing a balanced translocation t(X;4)(p21;q31).arr(1–22,X)x2 dn with breakpoint on the X-chromosome within an intron of the DMD gene. The inactivation of the nonderivative X-chromosome was found to be in a nonrandom pattern, resulting in a functionally balanced karyotype and thus leading to a manifesting DMD carrier in this case. Chromosome analysis should be recommended in cases of genetically unsolved DMD carriers as a part of the standard genetic procedures.

Supplementary Material

 
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