title: Gamma ray-induced loss of expression of HLA and glyoxalase I alleles in lymphoblastoid cells.
abstract: Gamma rays from a cesium source were used to generate human lymphoblastoid cell line variants that had lost expression of all major histocompatibility complex antigens coded for by a single haplotype. The cell line was heterozygous at the glyoxalase I locus and had the HLA haplotypes HLA-A1, B8, DRw3, and HLA-A2, B5, DRw1. We selected with anti-HLA-B8 antiserum in a population of cells that had been irradiated with 300 R. The incidence of B8-loss variants was 4.1 X 10(-5) on day 5 after irradiation. Analysis of variants showed that expressions of HLA and GLO alleles trans to B8 were retained. However, expression of additional cis-linked HLA and GLO gene products was lost in 12 of 17 variants. Variants that had lost expression of (i) HLA-B8, (ii) HLA-B8, A1, (iii) HLA-B8, A1, DRw3, or (iv) HLA-B8, A1, DRw3 and the cis-linked glyoxalase I allele were obtained. Karyotype analysis was performed on eight variants that had lost expression of two or more cis-linked alleles. Three variants had two normal appearing no. 6 chromosomes, four variants had a deletion that included the region coding for HLA genes on the short arm of one no. 6 chromosome, and one variant had an inversion or translocation involving the short arm of one no. 6.
mesh_terms: D002460:Cell Line; D002872:Chromosome Deletion; D007446:Chromosome Inversion; D002902:Chromosomes, Human, 16-18; D002906:Chromosomes, Human, 6-12 and X; D005720:Gamma Rays; D005796:Genes / Q000528:radiation effects*; D006680:HLA Antigens / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D007791:Lactoylglutathione Lyase / Q000235:genetics*; D008190:Lyases / Q000235:genetics*; D008214:Lymphocytes / Q000528:radiation effects*; D009154:Mutation
chemical_list: D006680:HLA Antigens; D008190:Lyases; D007791:Lactoylglutathione Lyase