Presented by

Dr. Carsten G. Bönnemann

Congenital muscular dystrophies (CMD) are a genetically heterogeneous group of disorders of voluntary muscle presenting at birth or in early infancy with weakness and evidence for a dystrophic myopathy on the muscle biopsy. Initially recognized more than a hundred years ago, considerable progress in the elucidation of molecular mechanisms has been more recent. An emerging theme amongst gene products involved in the pathogenesis of CMD is their involvement with the extracellular matrix of muscle. Three of the main forms affect molecular components that mediate the interaction of the muscle fibers with the extracellular matrix: Merosin (laminin211) deficient CMD caused by mutations in LAMA2, the alpha-dystroglycanopathies caused by mutations in genes involved in O-mannosyl linked glycosylation of the laminin211 receptor  alpha-dystroglycan, and the collagen VI related muscular dystrophies, caused by mutations in the genes COL6A1, A2, and A3. These CMDs of the extracellular matrix collectively represent the most common forms. This presentation will highlight recent developments including the discovery of novel genes, define and expanded clinical spectra, and highlight new developments towards therapeutic approaches.