Abstract |
X-linked myotubular myopathy is a congenital muscle disorder due to MTM1 mutation, and is characterized clinically by generalized muscle weakness and hypotonia at birth usually resulting in early death. We newly identified 26 unrelated Japanese patients with MTM1 mutations by genomic DNA and transcript analysis, including 12 novel mutations. Among 31 patients, including our previously reported five patients, the c.1261-10A>G splice site mutation was the most frequent mutation. Three mutations, one missense and two splice site, were associated with milder phenotype. Of particular interest, one boy had a 240 kb deletion in Xq28 encompassing CXorf6 (formerly F18), MTM1 and MTMR1 but was not accompanied by hypogenitalism. CXorf6, which have been implicated in male sexual development, was not entirely deleted in this boy, resulting in the fusion with the MTMR1 gene. A chimeric fusion transcript was detected in patient's muscle by RT-PCR, suggesting this fusion gene product avoids the phenotype. This deletion led us to refine the critical region of CXorf6 for the development of male genitalia.
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Authors | Tzung-Chang Tsai, Hideo Horinouchi, Satoru Noguchi, Narihiro Minami, Kumiko Murayama, Yukiko K Hayashi, Ikuya Nonaka, Ichizo Nishino |
Journal | Neuromuscular disorders : NMD
(Neuromuscul Disord)
Vol. 15
Issue 3
Pg. 245-52
(Mar 2005)
ISSN: 0960-8966 [Print] England |
PMID | 15725586
(Publication Type: Comparative Study, Journal Article)
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Chemical References |
- DNA, Recombinant
- RNA, Messenger
- Protein Tyrosine Phosphatases
- Protein Tyrosine Phosphatases, Non-Receptor
- myotubularin
- Glucan 1,3-beta-Glucosidase
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Topics |
- Adolescent
- Adult
- Child
- Child, Preschool
- Chromosome Mapping
- Chromosomes, Human, X
- DNA Mutational Analysis
- DNA, Recombinant
- Family Health
- Glucan 1,3-beta-Glucosidase
- Humans
- Infant
- Infant, Newborn
- Japan
- Male
- Middle Aged
- Muscles
(pathology)
- Mutation, Missense
- Myopathies, Structural, Congenital
(genetics)
- Phenotype
- Protein Tyrosine Phosphatases
(genetics)
- Protein Tyrosine Phosphatases, Non-Receptor
- RNA, Messenger
(biosynthesis)
- Reverse Transcriptase Polymerase Chain Reaction
(methods)
- Sequence Deletion
(genetics)
- Sex Chromosome Aberrations
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