Myoclonus-dystonia syndrome: ε-sarcoglycan mutations and phenotype

Mutations in the gene for ε‐sarcoglycan (SGCE) have been found to cause myoclonus‐dystonia syndrome. We now report clinical and genetic findings in nine additional European families with myoclonus‐dystonia syndrome. The clinical presentation in 24 affecteds was homogeneous with myoclonus predominantly of neck and upper limbs in 23 of them and dystonia, presenting as cervical dystonia and/or writer's cramp, in 13 cases. Six novel and one previously known heterozygous SGCE mutations were identified. SGCE deficiency seems to be the common pathogenetic mechanism in myoclonus‐dystonia syndrome.