Mutations of tropomyosin 3 (TPM3) are common and associated with type 1 myofiber hypotrophy in congenital fiber type disproportion.
Hum Mutat
; 31(2): 176-83, 2010 Feb.
Article
em En
| MEDLINE
| ID: mdl-19953533
ABSTRACT
Congenital fiber type disproportion (CFTD) is a rare congenital myopathy characterized by hypotonia and generalized muscle weakness. Pathologic diagnosis of CFTD is based on the presence of type 1 fiber hypotrophy of at least 12% in the absence of other notable pathological findings. Mutations of the ACTA1 and SEPN1 genes have been identified in a small percentage of CFTD cases. The muscle tropomyosin 3 gene, TPM3, is mutated in rare cases of nemaline myopathy that typically exhibit type 1 fiber hypotrophy with nemaline rods, and recently mutations in the TPM3 gene were also found to cause CFTD. We screened the TPM3 gene in patients with a clinical diagnosis of CFTD, nemaline myopathy, and with undefined congenital myopathies. Mutations in TPM3 were identified in 6 out of 13 patients with CFTD, as well as in one case of nemaline myopathy. Review of muscle biopsies from patients with diagnoses of CFTD revealed that patients with a TPM3 mutation all displayed marked disproportion of fiber size, without type 1 fiber predominance. Several mutation-negative cases exhibited other abnormalities, such as central nuclei and central cores. These results support the utility of the CFTD diagnosis in directing the course of genetic testing.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Tropomiosina
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Miopatias da Nemalina
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Fibras Musculares Esqueléticas
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Predisposição Genética para Doença
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Miopatias Congênitas Estruturais
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Mutação
Tipo de estudo:
Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Child
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Female
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Humans
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Infant
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Male
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Middle aged
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Newborn
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article