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Disease definition

A rare autosomal recessive cerebellar ataxia due to a DNA repair defect characterized by progressive neurological impairment with cerebellar syndrome, oculocutaneous telangiectasia, defects in B and T cell-mediated immunity, and increased susceptibility to malignancies (mainly lymphoid neoplasms). High sensitivity to ionizing radiation limits patient treatments.


Classification level: Disorder
  • Synonym(s):
    • Louis-Bar syndrome
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Childhood
  • ICD-10: G11.3
  • ICD-11: 4A01.31
  • OMIM: 208900  208910
  • UMLS: C0004135
  • MeSH: D001260
  • GARD: 5862
  • MedDRA: 10003594

Detailed information

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Disease review articles


Genetic Testing

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