title: Lack of association of delta-aminolevulinic acid dehydratase genotype with blood lead levels in environmentally exposed children of Uygur and Han populations.
abstract: OBJECTIVE
  A cross-section study was conducted to explore the association between polymorphism of delta-aminolevulinic acid dehydratase (ALAD) and lead poisoning in Uygur and Han children in China.
  
  
  METHODS
  The ALAD genotyping was determined by PCR-RFLP in 443 Uygur and 469 Han children aged 6-10 years from Urumqi in Xinjiang province.
  
  
  RESULTS
  The blood lead levels of 912 environmentally exposed children ranged from 0.5 to 48.2 microg/dL, with a mean of 5.45 microg/dL and a standard deviation of 0.22 microg/dL, and 23. Thirty-one percent individuals were with blood lead level > or =10 microg/dL. The mean and standard deviation of blood lead levels were 5.57 +/- 0.223 microg/dL and 5.30 +/- 0.224 microg/dL in Uygur and Han children, respectively. The frequencies of the allele ALAD1 and ALAD2 in Uygur subjects were 90.52% and 9.48%, and in Han subjects were 95.73% and 4.27%, respectively (chi-square = 19.55, p < 0.05). No statistic correlation between the distribution of ALAD alleles and the blood lead level was found in both populations.
  
  
  CONCLUSIONS
  A significant difference was seen in the frequency distribution of ALAD genotype between the different races. The genetic susceptibility of ALAD polymorphism to lead toxicity may exhibit in a lead dose-dependent manner.
authors.affiliation: Department of Toxicology, School of Public Health, Xinjiang Medical University, Urumqi, Xinjiang, China. ychen88@hotmail.com
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Jiang-Xia
authors.initials: JX
authors.lastname: Zhao
authors.forename: Ji-Wen
authors.initials: JW
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Cui
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.forename: Wei
authors.initials: W
authors.lastname: Tian
mesh_terms: D002648:Child; D002681:China; D003430:Cross-Sectional Studies; D004781:Environmental Exposure; D005260:Female; D005838:Genotype; D006801:Humans; D007854:Lead / Q000097:blood; D007855:Lead Poisoning / Q000097:blood* / Q000208:ethnology / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D000623:Porphobilinogen Synthase / Q000097:blood* / Q000235:genetics*; D012307:Risk Factors; D011795:Surveys and Questionnaires
chemical_list: D007854:Lead; D000623:Porphobilinogen Synthase