人类白细胞抗原DQ基因多态性与三氯乙烯药疹样皮炎易感性的关系

目的研究人类白细胞抗原DQ（HLA-DQ）基因多态性与三氯乙烯药疹样皮炎易感性的关系。方法应用聚合酶链反应产物直接测序方法,比较112例三氯乙烯药疹样皮炎病例和142例健康三氯乙烯接触工人HLA—DQA1和HLA—DQBl基因第2外显子氨基酸密码子多态性及等位基因型频率分布。结果病例组DQA1等位基因0201和060101／0602的分布频率7．6％（17／224）和16．1％（36／224）]显著高于对照组3．5％（10／284）和7．0％（20／284）],而病例组DQAl等位基因0103和050101／0503／0505的分布频率5．8％（13／224）和8．9％（20／224）]显著低于对照组10．9％（31／284）和17．3％（49／284）]。此外,病例组与对照组之间差异有统计学意义的氨基酸密码子多态性位点见于DQA1的5个密码子（25、41、52、54和69）。病例组与对照组HLA-DQB1等位基因的分布频率差异无统计学意义。结论HLA-DQA1基因多态性可能是导致三氯乙烯药疹样皮炎个体易感性差异的原因之一。

Possible association between polymorphisms of human leukocyte antigen-DQ genes and susceptibility to trichloroethylene-induced severe generalized dermatitis

Objective To investigate the association between genetic polymorphisms of human leukocyte antigen-DQ(HLA-DQ) and susceptibility to trichloroethylene (TCE)-induced severe generalized dermatitis. Methods A case-control study was conducted which included 112 patients with TCE-induced severe generalized dermatitis and 142 healthy controls exposed to TCE in the same workshop. The DNA sequences in exon2 of HLA-DQA1 and HLA-DQB1 were performed by direct sequencing of polymerase chain reaction (PCR) products. The frequencies distribution of allelic genotypes and codon polymorphisms were compared. Results The frequencies of DQA1*0201 and 060101/0602 in cases 7.6% (17/224) and 16.1% (36/224)] were significantly higher than those of the exposed controls 3.5% (10/284) and 7.0% (20/284)], while frequencies of DQA1*0103 and 050101/0503/0505 in cases 5.8% (13/224) and 8.9% (20/224)] were significantly lower than those of exposed controls 10.9% (31/284) and 17.3% (49/284)]. In terms of codon polymorphisms,there were 5 codons of DQA1(25,41,52,54 and 69)showing significant differences between cases and controls. There were no significant differences in the frequencies of allelic genotypes of HLA-DQB1 between cases and exposed controls. Conclusion The genetic polymorphisms of HLA-DQA1 might be one of the factors influencing the individual susceptibility to TCE- induced severe generalized dermatitis.