Futakami Masae, Salimullah Md, Miura Takashi, Tokita Sumio, Nishigaki Koichi
Department of Functional Materials Science, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan.
J Biochem. 2007 May;141(5):675-86. doi: 10.1093/jb/mvm074. Epub 2007 Mar 23.
Almost all of the methodologies developed to date to assay the potential mutagenicity of chemical substances are based on detection of altered phenotypic traits. The alternative approach of directly screening the whole genome for mutations is not feasible because of the logistics of carrying out mass sequencing of genes. Here we describe a novel and highly sensitive mutation assay, which we term the 'genome profiling-based mutation assay' (GPMA) that directly detects mutations generated in genomic DNA. We used GPMA to detect mutations caused by known mutagens such as AF2 and ethidium bromide even at concentrations of 30 ppb. The number of mutations detected was dependent on the number of generations in culture and the concentrations of the mutagens. Almost complete agreement was observed between GPMA and the Ames test in the discrimination of mutagens (63 out of 64). Owing to the high sensitivity of GPMA, the effects of long-term and low-dose exposures and the influence of chemicals of low solubility can also be screened. Thus, genotype-based GPMA can complement the Ames test, which is the standard technology in this field and is based on phenotypic traits.
迄今为止，几乎所有用于检测化学物质潜在致突变性的方法都是基于对改变的表型特征的检测。由于对基因进行大规模测序的操作难度，直接对全基因组进行突变筛选的替代方法并不可行。在此，我们描述了一种新颖且高度灵敏的突变检测方法，我们将其称为“基于基因组图谱的突变检测法”（GPMA），该方法可直接检测基因组DNA中产生的突变。我们使用GPMA检测已知诱变剂（如AF2和溴化乙锭）在浓度低至30 ppb时所引起的突变。检测到的突变数量取决于培养代数和诱变剂浓度。在区分诱变剂方面，GPMA与艾姆斯试验之间观察到几乎完全一致的结果（64种中有63种）。由于GPMA具有高灵敏度，因此还可以筛选长期低剂量暴露的影响以及低溶解度化学物质的影响。因此，基于基因型的GPMA可以补充艾姆斯试验，艾姆斯试验是该领域基于表型特征的标准技术。
