Objective The aim of this study is to identify the molecular defect of three unrelated individuals with late-onset predominant distal myopathy; to describe the spectrum of phenotype resulting from the contributing role of two variants in genes located on two different chromosomes; and to highlight the underappreciated complex forms of genetic myopathies. Patients and methods Clinical and labo...

INTRODUCTION Miyoshi myopathy, a type of distal myopathy with predominant involvement of the posterior calf muscles, has been assigned to mutations in the dysferlin gene. However, many of the late-onset limb-girdle and distal myopathies that resemble dysferlinopathy or Miyoshi myopathy remain unclassified, even after extensive immunohistological and genetic analysis. CASE PRESENTATION We repo...

The term congenital myopathy is applied to muscle disorders presenting with generalized muscle weakness and hypotonia from early infancy with delayed developmental milestones. The congenital myopathies have been classified into various categories based on morphological findings on muscle biopsy. Although the clinical symptoms may seem homogenous, the genetic basis is remarkably variable. This r...

Wenz T, Diaz F, Hernandez D, Moraes CT. Endurance exercise is protective for mice with mitochondrial myopathy. J Appl Physiol 106: 1712–1719, 2009. First published March 12, 2009; doi:10.1152/japplphysiol.91571.2008.—Defects in the mitochondrial ATP-generating system are one of the most commonly inherited neurological disorders, but they remain without treatment. We have recently shown that mod...

GNE myopathy (previous names: HIBM, DMRV, IBM2) is a unique distal myopathy with quadriceps sparing. This recessively inherited myopathy has been diagnosed in various regions of the world with more than 150 disease-causing mutations already identified. Several of those are proven or suspected to be founder mutations in certain regional clusters and are described in this review. The review also ...

Hereditary inclusion body myopathy (hIBM) is an adult-onset hereditary myopathy, usually with distal onset and quadriceps sparing. This myopathy is autosomal recessive and associated to UPD-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase (GNE) gene mutations. In this study, we report a novel GNE homozygous point mutation c.1834T>G that results in amino acid substitution of cysteine 6...

Hypothyroid myopathy has so far been reported in long standing cases of hypothyroidism. We describe two adult patients with myopathy associated with acute transient hypothyroidism. Both presented with severe muscle aches and cramps, stiffness and spasms. Muscle enzymes were markedly elevated and electromyography in one patient showed myopathic features. Histological changes were absent in muscl...

Centronuclear myopathy (CNM) is a rare congenital myopathy that is characterized by centrally placed nuclei in the muscle fibers. Three forms of the disease are clinically recognized. The severe neonatal form, the childhood onset form, and an adult-onset form. We report a 50 year old male patient with centronuclear myopathy (CNM) in whom the disease manifested itself in the fifth decade of life...