Intellectual disability-hyperkinetic movement-truncal ataxia syndrome

What is Intellectual disability-hyperkinetic movement-truncal ataxia syndrome?

A rare, genetic, syndromic intellectual disability disease characterized by global developmental delay, microcephaly, mild to moderate intellectual disability, truncal ataxia, trunk and limb, or generalized, choreiform movements, and elevated serum creatine kinase levels. Variably associated features include mild cerebral atrophy, muscular weakness or hypotonia in early childhood, and/or seizures. Ocular abnormalities (e.g. exophoria, anisometropia, amblyopia) have been reported.

Inheritance type

Autosomal recessive


  • Worldwide: <1 in 1,000 000

Age of Onset

  • Childhood
Orphadata: Free access data from Orphanet. © INSERM 1999. Available on "". Data version 1.3.16 / 4.1.7.