title: HPRT mutations in lymphocytes from 1,3-butadiene-exposed workers in China.
abstract: BACKGROUND
  1,3-Butadiene (BD) is an important industrial chemical and an environmental and occupational pollutant. The carcinogenicity of BD in rodents has been proved, but its carcinogenic and mutagenic molecular mechanism(s) are not fully elucidated in humans.
  
  
  OBJECTIVE
  In the present study, we compared the mutation frequencies and exon deletions of BD-exposed workers with that of control subjects in China to identify the characteristic mutations associated with BD exposure in the human HPRT (hypoxanthine-guanine-phosphoribosyltransferase) gene.
  
  
  METHODS
  Seventy-four workers exposed to BD via inhalation and 157 matched controls were evaluated in Nanjing, China. Molecular analysis of HPRT mutant T lymphocytes from BD-exposed workers and nonexposed control subjects was conducted to identify changes in the structure of the HPRT gene. A total of 783 HPRT mutants were analyzed by multiplex polymerase chain reaction, in which 368 HPRT mutants were isolated from BD-exposed workers and 415 mutants from control subjects.
  
  
  RESULTS
  The BD-exposed workers showed a higher mutation frequency (18.2 +/- 9.4 x 10(-6)) than the control subjects (12.7 +/- 7.3 x 10(-6)), but the difference was not significant (p > 0.05). The frequency of exon deletions in BD-exposed workers (27.4%) was significantly higher than that in control subjects (12.5%) (p < 0.05), which mainly included multiplex exon deletions (2-8 exons).
  
  
  CONCLUSIONS
  The results of the present study suggest that BD should increase the frequency of large deletions of HPRT gene in human lymphocytes This change confirms and supports the previous findings in BD-exposed workers.
authors.affiliation: Department of Hygienic Toxicology, Preventive Medical College, Third Military Medical University, Chongqing, People's Republic of China.
authors.forename: Shengxue
authors.initials: S
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Ao
authors.forename: Bing
authors.initials: B
authors.lastname: Du
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Zhou
authors.forename: Jian
authors.initials: J
authors.lastname: Yuan
authors.forename: Yang
authors.initials: Y
authors.lastname: Bai
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Zhou
authors.forename: Jia
authors.initials: J
authors.lastname: Cao
mesh_terms: D002681:China; D005260:Female; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics*; D008214:Lymphocytes / Q000201:enzymology*; D008297:Male; D009154:Mutation; D016273:Occupational Exposure; D016133:Polymerase Chain Reaction
chemical_list: D007041:Hypoxanthine Phosphoribosyltransferase