Very mild presentation in adult with classical cellular phenotype of ataxia telangiectasia

Mov Disord. 2013 Apr;28(4):524-8. doi: 10.1002/mds.25236. Epub 2012 Nov 9.


Background: The major clinical feature of ataxia telangiectasia (A-T) is severe progressive neurodegeneration with onset in infancy. This classical A-T phenotype is caused by biallelic null mutations in the ATM gene, leading to the absence of ATM protein and increased cellular radiosensitivity. We report an unusual case of A-T in a 41-year-old mother, A-T210, who had very mild neurological symptoms despite complete loss of ATM protein.

Methods: A neurological examination was performed, cellular radiosensitivity was assessed, and the ATM gene was sequenced. Skin fibroblasts and a lymphoblastoid cell line (LCL) were assayed for ATM protein expression and kinase activity.

Results: Patient A-T210 showed mild chorea, dystonia, and gait ataxia, walked independently, and drove a car. LCL and skin fibroblasts were radiosensitive and did not express ATM protein. Two ATM-null mutations were identified.

Conclusions: The severe neurodegeneration resulting from loss of ATM can be mitigated in some circumstances.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Ataxia Telangiectasia / diagnosis
  • Ataxia Telangiectasia / genetics*
  • Ataxia Telangiectasia / metabolism
  • Ataxia Telangiectasia Mutated Proteins / metabolism
  • Cell Line
  • Female
  • Genotype
  • Humans
  • Mutation / genetics*
  • Phenotype
  • Radiation Tolerance


  • Ataxia Telangiectasia Mutated Proteins