Myotonia congenita in northern Finland: an epidemiological and genetic study.

Clinical and genetic investigations of patients with myotonia congenita in Northern Norway

A Novel Missense Mutation in CLCN1 Gene in a Family with Autosomal Recessive Congenital Myotonia

Congenital recessive myotonia is a rare genetic disorder caused by mutations in CLCN1, which codes for the main skeletal muscle chloride channel ClC-1. More than 120 mutations have been found in this gene. The main feature of this disorder is muscle membrane hyperexcitability. Here, we report a 59-year male patient suffering from congenital myotonia. He had transient generalized myotonia, which...

Becker's variant of myotonia congenita in two siblings--a clinico-genetic study.

We report a family of a brother and sister of myotonia congenita, conforming to autosomal recessive transmission (Becker's variety). To the best of our knowledge, no account of a family of autosomal recessive myotonia (Becker's disease), has earlier been reported from India.

Whole-body high-field MRI shows no skeletal muscle degeneration in young patients with recessive myotonia congenita.

BACKGROUND Muscle magnetic resonance imaging (MRI) is the most sensitive method in the detection of dystrophic and non-dystrophic abnormalities within striated muscles. We hypothesized that in severe myotonia congenita type Becker muscle stiffness, prolonged transient weakness and muscle hypertrophy might finally result in morphologic skeletal muscle alterations reflected by MRI signal changes....

Transient weakness and compound muscle action potential decrement in myotonia congenita.

Twenty-five Turkish patients with recessive myotonia congenita (RMC), 16 of whom had genetic confirmation, were studied. Nineteen had transient weakness. In the upper extremities, onset age of transient weakness was usually in the early teens. All untreated RMC patients had a compound muscle action potential decrement of > or =25%, usually above 50%, with repetitive nerve stimulation at 10/s fo...