X-linked Myotubular Myopathy: a Novel Mutation in the MTM-1 Gene – Case Reports

Czech version

Authors: P. Laššuthová ¹; V. Sebroň ²; J. Zámečník ³; J. Haberlová ¹; A. Baxová ⁴; P. Seeman ¹
Authors‘ workplace: DNA laboratoř Kliniky dětské neurologie 2. LF UK a FN v Motole, Praha ¹; Novorozenecké oddělení Gynekologicko-porodnické kliniky 1. LF UK a VFN v Praze ²; Ústav patologie a molekulární medicíny 2. LF UK a FN v Motole, Praha ³; Ústav biologie a lékařské genetiky 1. LF UK a VFN v Praze ⁴
Published in: Cesk Slov Neurol N 2013; 76/109(2): 241-245
Category: Case Report

Overview

Mutations in the MTM1 gene cause X-linked myotubular myopathy (XLMTM). This is a serious, often lethal, condition. We report a family with two affected children – dizygotic twins. Boys were born in the 28^th gestational week. Severe hypotonia and muscle weakness were present at birth and necessitated ventilatory support. Intensive care was terminated 26 and 35 days after birth, respectively, due to cardiac and renal failure. Hypotrophic muscle fibers, fetal myotubes and centrally located nuclei were present in muscle sections. All the available information led us to the diagnosis of XLMTM. The MTM1 gene was sequenced and a novel mutation c.82delA in exon 3 was identified. The mother of the patients is a heterozygous carrier of the mutation. This might well be the first report of genetically confirmed XLMTM in the Czech Republic. DNA test is now available and prenatal or preimplantation diagnosis might be offered to the family.

Key words:
MTM1 gene – myotubular myopathy – frameshift mutation

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