Autosomal recessive cerebellar ataxia with oculomotor apraxia (ataxia-telangiectasia-like syndrome) is linked to chromosome 9q34

Am J Hum Genet. 2000 Nov;67(5):1320-6. doi: 10.1016/S0002-9297(07)62962-0. Epub 2000 Oct 5.


Ataxia with oculomotor apraxia (ataxia-telangiectasia-like syndrome [AOA]; MIM 208920) is an autosomal recessive disorder characterized by ataxia, oculomotor apraxia, and choreoathetosis. These neurological features resemble those of ataxia-telangiectasia (AT), but in AOA there are none of the extraneurological features of AT, such as immunodeficiency, neoplasia, chromosomal instability, or sensitivity to ionizing radiation. It is unclear whether these patients have a true disorder of chromosomal instability or a primary neurodegenerative syndrome, and it has not been possible to identify the defective gene in AOA, since the families have been too small for linkage analysis. We have identified a new family with AOA, and we show that the patients have no evidence of chromosomal instability or sensitivity to ionizing radiation, suggesting that AOA in this family is a true primary cerebellar ataxia. We have localized the disease gene, by linkage analysis and homozygosity mapping, to a 15.9-cM interval on chromosome 9q34. This work will ultimately allow the disease gene to be identified and its relevance to other types of autosomal recessive cerebellar ataxias to be determined.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acid Anhydride Hydrolases
  • Apraxias / genetics*
  • Apraxias / physiopathology
  • Ataxia Telangiectasia / genetics*
  • Ataxia Telangiectasia / physiopathology
  • Ataxia Telangiectasia Mutated Proteins
  • Cell Cycle Proteins
  • Cerebellar Ataxia / genetics*
  • Cerebellar Ataxia / physiopathology
  • Chromosome Mapping
  • Chromosomes, Human, Pair 9 / genetics*
  • Consanguinity
  • DNA Damage / radiation effects
  • DNA Repair Enzymes*
  • DNA-Binding Proteins / genetics
  • Female
  • Genes, Recessive / genetics*
  • Genetic Linkage / genetics*
  • Homozygote
  • Humans
  • Lod Score
  • Lymphocytes / metabolism
  • Lymphocytes / radiation effects
  • MRE11 Homologue Protein
  • Male
  • Nuclear Proteins / genetics
  • Pakistan
  • Pedigree
  • Protein Serine-Threonine Kinases / genetics
  • RNA, Messenger / analysis
  • RNA, Messenger / genetics
  • Syndrome
  • Tumor Suppressor Proteins
  • X-Rays


  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • MRE11 protein, human
  • Nuclear Proteins
  • RNA, Messenger
  • Tumor Suppressor Proteins
  • ATM protein, human
  • Ataxia Telangiectasia Mutated Proteins
  • Protein Serine-Threonine Kinases
  • MRE11 Homologue Protein
  • Acid Anhydride Hydrolases
  • Rad50 protein, human
  • DNA Repair Enzymes