title: Classification of mutations at the human hprt-locus in T-lymphocytes of bus maintenance workers by multiplex-PCR and reverse transcriptase-PCR analysis.
abstract: Polymerase chain reaction (PCR)-based screening methods were used to classify mutations arising in vivo at the hypoxanthine guanine phosphoribosyl-transferase (hprt) locus in small samples of human T-lymphocyte clones (< 5 x 10(4) cells) from 29 bus maintenance workers exposed to diesel exhaust, and 14 control individuals. All subjects were healthy, non-smoking males. Among 462 T-cell mutants studied by multiplex-PCR of genomic DNA, only 12 (2.6%) deletions were found: three total deletions, five partial exon deletions and four mutants with one or two exons deleted. Point mutations were classified in 323 mutants using reverse transcriptase-PCR amplification: 74 (22.9%) of these had splice site mutations and 241 (74.6%) had coding errors. Splice mutation was more frequent among the garage workers (24.8%) as compared to the controls (19.5%), possibly reflecting a polycyclic aromatic hydrocarbon-specific mutation induction in these workers. Our results also show that both gene deletion and splice mutation at the hprt-locus in T-cells of healthy non-smokers could be less frequent than previously reported.
authors.affiliation: Karolinska Institutet, Department of Biosciences, NOVUM, Huddinge, Sweden.
authors.forename: A M
authors.initials: AM
authors.lastname: Osterholm
authors.forename: S
authors.initials: S
authors.lastname: Fält
authors.forename: B
authors.initials: B
authors.lastname: Lambert
authors.forename: S M
authors.initials: SM
authors.lastname: Hou
mesh_terms: D001483:Base Sequence; D018736:DNA Adducts / Q000032:analysis; D017353:Gene Deletion; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D016273:Occupational Exposure; D016133:Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000201:enzymology; D001335:Vehicle Emissions / Q000009:adverse effects*
chemical_list: D018736:DNA Adducts; D001335:Vehicle Emissions; D007041:Hypoxanthine Phosphoribosyltransferase