A mutation causes MuSK reduced sensitivity to agrin and congenital myasthenia.

Congenital myasthenic syndromes (CMSs) are a heterogeneous group of genetic disorders affecting neuromuscular transmission. The agrin/muscle-specific kinase (MuSK) pathway is critical for proper development and maintenance of the neuromuscular junction (NMJ). We report here an Iranian patient in whom CMS was diagnosed since he presented with congenital and fluctuating bilateral symmetric ptosis, upward gaze palsy and slowly progressive muscle weakness leading to loss of ambulation.

Multiexon deletions account for 15% of congenital myasthenic syndromes with RAPSN mutations after negative DNA sequencing.

Congenital myasthenic syndromes (CMS) are a heterogeneous group of genetic disorders that give rise to a defect in neuromuscular transmission. We described here three patients with a characteristic phenotype of recessive CMS and presenting mutation in the gene encoding rapsyn (RAPSN). Familial analysis showed that one allelic mutation failed to be detected by direct sequencing.

Identification of an agrin mutation that causes congenital myasthenia and affects synapse function.

We report the case of a congenital myasthenic syndrome due to a mutation in AGRN, the gene encoding agrin, an extracellular matrix molecule released by the nerve and critical for formation of the neuromuscular junction. Gene analysis identified a homozygous missense mutation, c.5125G>C, leading to the p.