title: Relation between the human fibroblast strain 46BR and cell lines representative of Bloom's syndrome.
abstract: 46BR is a human fibroblast strain derived from an immunodeficient young female of stunted growth. The diploid fibroblasts as well as a Simian Virus 40-transformed cell line are hypersensitive to killing by many DNA-damaging agents, exhibit a slightly increased level of spontaneous sister chromatid exchange, and show a defect in DNA ligation in vivo. 46BR is now shown to have abnormal DNA ligase I and is similar in this regard to cell lines derived from Bloom's syndrome patients. In a direct comparison, both 46BR and several Bloom's syndrome lines were found to be hypersensitive to the cytotoxic effect of simple alkylating agents, 46BR being more markedly sensitive. Bloom's syndrome lines do not exhibit the strong delay in joining of Okazaki fragments during DNA replication characteristic of 46BR. The cell line 46BR probably has a mutation in the gene encoding DNA ligase I different from those occurring in classical cases of Bloom's syndrome.
authors.affiliation: MRC Cell Mutation Unit, University of Sussex, Falmer, Brighton, United Kingdom.
authors.forename: A R
authors.initials: AR
authors.lastname: Lehmann
authors.forename: A E
authors.initials: AE
authors.lastname: Willis
authors.forename: B C
authors.initials: BC
authors.lastname: Broughton
authors.forename: M R
authors.initials: MR
authors.lastname: James
authors.forename: H
authors.initials: H
authors.lastname: Steingrimsdottir
authors.forename: S A
authors.initials: SA
authors.lastname: Harcourt
authors.forename: C F
authors.initials: CF
authors.lastname: Arlett
authors.forename: T
authors.initials: T
authors.lastname: Lindahl
mesh_terms: D001549:Benzamides / Q000494:pharmacology; D001816:Bloom Syndrome / Q000235:genetics*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004249:DNA Damage; D011088:DNA Ligases / Q000032:analysis; D004261:DNA Replication; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D008970:Molecular Weight; D009154:Mutation; D012854:Sister Chromatid Exchange; D013463:Sulfuric Acid Esters / Q000494:pharmacology
chemical_list: D001549:Benzamides; D013463:Sulfuric Acid Esters; C025160:3-aminobenzamide; D011088:DNA Ligases; C007482:dimethyl sulfate