Møller Peter
Institute of Public Health, University of Copenhagen, Øster Farimagsgade 5, Building B, 2nd Floor, P.O. Box 2099, DK-1014 Copenhagen K, Denmark.
Basic Clin Pharmacol Toxicol. 2006 Apr;98(4):336-45. doi: 10.1111/j.1742-7843.2006.pto_167.x.
Generation of DNA damage is considered to be an important initial event in carcinogenesis. The single cell gel electrophoresis (comet) assay is a technically simple and fast method that detects genotoxicity in virtually any mammalian cell type without requirement for cell culture. This review discusses the strength of the comet assay in biomonitoring at its present state of validation. The simple version of the alkaline comet assay detects DNA migration caused by strand breaks, alkaline labile sites, and transient repair sites. By incubation with bacterial glycosylase/endonuclease enzymes, broad classes of oxidative DNA damage, alkylations, and ultraviolet light-induced photoproducts are detected as additional DNA migration. The most widely measured enzyme sensitive sites have been those detected by formamidopyrimidine DNA glycosylase (FPG) and endonuclease III (ENDOIII). Reports from biomonitoring studies show that the basal level of DNA damage in leukocytes is influenced be a variety of lifestyle and environmental exposures, including exercise, air pollution, sunlight, and diet. Although not all types of carcinogenic exposures should be expected to damage DNA in leukocytes, the comet assay is a valuable method for detection of genotoxic exposure in humans. However, the predictive value of the comet assay is unknown because it has not been investigated in prospective cohort studies. Also, it is important that the performance of the assay is investigated in multi-laboratory validation trials. As a tool in risk assessment the comet assay can be used in characterization of hazards.
DNA损伤的产生被认为是致癌过程中一个重要的起始事件。单细胞凝胶电泳（彗星）试验是一种技术简单且快速的方法，可在几乎任何哺乳动物细胞类型中检测遗传毒性，无需细胞培养。本综述讨论了彗星试验在目前验证状态下用于生物监测的优势。碱性彗星试验的简单版本可检测由链断裂、碱性不稳定位点和瞬时修复位点引起的DNA迁移。通过与细菌糖基化酶/核酸内切酶孵育，可检测到广泛类别的氧化性DNA损伤、烷基化和紫外线诱导的光产物，这些都会导致额外的DNA迁移。测量最广泛的酶敏感位点是由甲酰胺嘧啶DNA糖基化酶（FPG）和核酸内切酶III（ENDOIII）检测到的那些位点。生物监测研究报告表明，白细胞中DNA损伤的基础水平受多种生活方式和环境暴露的影响，包括运动、空气污染、阳光和饮食。虽然并非所有致癌性暴露都应预期会损伤白细胞中的DNA，但彗星试验是检测人类遗传毒性暴露的一种有价值的方法。然而，彗星试验的预测价值尚不清楚，因为尚未在前瞻性队列研究中进行调查。此外，在多实验室验证试验中研究该试验的性能也很重要。作为风险评估的一种工具，彗星试验可用于危害特征描述。
