title: Radiosensitive Down syndrome lymphoblastoid lines have normal ionizing-radiation-induced inhibition of DNA synthesis.
abstract: The extent of X-ray-induced inhibition of DNA synthesis was determined in radiosensitive lymphoblastoid lines from 3 patients with Down syndrome and 3 patients with ataxia telangiectasia (AT). Compared to 6 normal control lines, the 3 AT lines were abnormally resistant to X-ray-induced inhibition of DNA synthesis, while the 3 Down syndrome lines had normal inhibition. These results demonstrate that radiosensitive human cells can have normal X-ray-induced inhibition of DNA synthesis and provide new evidence for the dissociation of radiosensitivity from radioresistant DNA synthesis.
authors.affiliation: Dermatology Branch National Cancer Institute, Bethesda, MD 20892.
authors.forename: M B
authors.initials: MB
authors.lastname: Ganges
authors.forename: R E
authors.initials: RE
authors.lastname: Tarone
authors.forename: H X
authors.initials: HX
authors.lastname: Jiang
authors.forename: C
authors.initials: C
authors.lastname: Hauser
authors.forename: J H
authors.initials: JH
authors.lastname: Robbins
mesh_terms: D001260:Ataxia Telangiectasia / Q000235:genetics*; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D004260:DNA Repair; D004261:DNA Replication / Q000187:drug effects*; D004307:Dose-Response Relationship, Radiation; D004314:Down Syndrome / Q000235:genetics*; D006801:Humans; D014965:X-Rays