title: Ataxia-oculomotor apraxia 2 patients show no increased sensitivity to ionizing radiation.
abstract: Mutations in senataxin have been described recently in 24 cases of French-Canadian descent with ataxia-oculomotor apraxia 2. This recessive ataxia is associated with an elevation in alpha-fetoprotein as in ataxia-telangiectasia. Because ataxia-telangiectasia cells are highly radiosensitive, we used a colony survival assay to measure the radiosensitivity of lymphoblastoid cell lines derived from five French-Canadian patients with ataxia-oculomotor apraxia 2. Two were homozygous for the common French-Canadian L1976R SETX missense mutation; the three others were compound heterozygotes for the common mutation and three different missense mutations. Overall, lymphoblastoid cell lines derived from these cases did not show significant variation from a normal response to 1 Gray of ionizing radiation but the two patients who were homozygous for the common L1976R mutation fell in the intermediate or non-diagnostic range.
authors.affiliation: UCLA School of Medicine, Department of Pathology & Laboratory Medicine, Macdonald Research Laboratories, Los Angeles, CA, USA.
authors.forename: S A
authors.initials: SA
authors.lastname: Nahas
authors.forename: A
authors.initials: A
authors.lastname: Duquette
authors.forename: K
authors.initials: K
authors.lastname: Roddier
authors.forename: R A
authors.initials: RA
authors.lastname: Gatti
authors.forename: B
authors.initials: B
authors.lastname: Brais
mesh_terms: D000293:Adolescent; D001072:Apraxias / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D001259:Ataxia / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D002460:Cell Line; D002648:Child; D003114:Colony-Forming Units Assay / Q000379:methods; D004265:DNA Helicases; D004252:DNA Mutational Analysis; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006801:Humans; D008214:Lymphocytes / Q000502:physiology / Q000528:radiation effects; D064251:Multifunctional Enzymes; D009154:Mutation / Q000235:genetics; D009369:Neoplasms / Q000175:diagnosis / Q000235:genetics; D015835:Ocular Motility Disorders / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D011379:Prognosis; D011792:Quebec / Q000208:ethnology; D020365:RNA Helicases / Q000235:genetics; D011839:Radiation, Ionizing; D000509:alpha-Fetoproteins / Q000235:genetics
chemical_list: D064251:Multifunctional Enzymes; D000509:alpha-Fetoproteins; C484368:SETX protein, human; D004265:DNA Helicases; D020365:RNA Helicases