title: Very mild presentation in adult with classical cellular phenotype of ataxia telangiectasia.
abstract: 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.
authors.affiliation: Department of Neurology, Norfolk and Norwich University Hospital, Norwich, United Kingdom.
authors.forename: Paul F
authors.initials: PF
authors.lastname: Worth
authors.forename: Venkataramanan
authors.initials: V
authors.lastname: Srinivasan
authors.forename: Anna
authors.initials: A
authors.lastname: Smith
authors.forename: James I
authors.initials: JI
authors.lastname: Last
authors.forename: Laura L
authors.initials: LL
authors.lastname: Wootton
authors.forename: Paul M
authors.initials: PM
authors.lastname: Biggs
authors.forename: Nicholas P
authors.initials: NP
authors.lastname: Davies
authors.forename: Ellen F
authors.initials: EF
authors.lastname: Carney
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Byrd
authors.forename: A Malcolm R
authors.initials: AM
authors.lastname: Taylor
mesh_terms: D000328:Adult; D001260:Ataxia Telangiectasia / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D064007:Ataxia Telangiectasia Mutated Proteins / Q000378:metabolism; D002460:Cell Line; D005260:Female; D005838:Genotype; D006801:Humans; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D011836:Radiation Tolerance
chemical_list: D064007:Ataxia Telangiectasia Mutated Proteins