Inherited myotonic disorders with early childhood onset MYOTONIA. Muscular hypertrophy is common and myotonia may impair ambulation and other movements. It is classified as Thomsen (autosomal dominant) or Becker (autosomal recessive) generalized myotonia mainly based on the inheritance pattern. Becker type is also clinically more severe. An autosomal dominant variant with milder symptoms and later onset is known as myotonia levior. Mutations in the voltage-dependent skeletal muscle chloride channel are associated with the disorders.
Also Known As:
Thomsen Disease; Batten Turner Congenital Myopathy; Batten-Turner Congenital Myopathy; Becker Disease; Congenital Myotonia; Generalized Myotonia of Becker; Generalized Myotonia of Thomsen; Myopathy, Congenital; Myotonia Congenita, Autosomal Dominant; Myotonia Congenita, Autosomal Recessive; Myotonia Levior; Myotonia, Generalized; Thomsen's Disease; Thomsens Disease; Disease, Becker; Disease, Thomsen; Disease, Thomsen's; Disease, Thomsens; Generalized Myotonia; Generalized Myotonia, Becker; Generalized Myotonias; Myotonia, Becker Generalized; Myotonias, Generalized; Thomsen Generalized Myotonia; Becker Generalized Myotonia; Myotonia, Generalized, Becker