Kumar Amod, Kesari Vibudh P, Alok Ashok Kumar, Kazim Syed N, Khan Parimal K
Toxicogenetics Laboratory, Department of Zoology, Patna University, Patna, 800 005, India.
Arch Environ Contam Toxicol. 2014 Nov;67(4):630-8. doi: 10.1007/s00244-014-0051-5. Epub 2014 Jun 26.
Arsenic is a groundwater contaminant of global concern. It is a potent human carcinogen, and its marked genotoxic effects have been reported in several human and animal studies. The present work investigates the applicability of the random amplified polymorphic DNA (RAPD) assay to study the DNA-damaging effects of arsenic at low-level exposure in goldfish Carassius auratus. Four experimental groups of fish, A, B, C and D, were exposed to 0, 10, 50, and 1,000 µg L(-1) of arsenic, respectively, in aquaria water for 15 consecutive days. Genomic DNA extraction was followed by RAPD-polymerase chain reaction amplification for each fish separately. One arbitrary decamer primer (PUZ-19) of 33 primers used appeared as the most informative and was capable of exhibiting marked alterations in RAPD profiles between arsenic-exposed and unexposed (control) samples. Different sets of 11 loci were amplified in various experimental groups with four clear polymorphic bands by the primer PUZ-19. The X and XIII amplification loci, which were prominent in the unexposed group, failed to appear in the arsenic-exposed groups. In contrast, the I and XI RAPD bands appeared as new amplification loci in all of the exposed groups. Such alterations in genomic DNA, however, did not exhibit a clear dose-dependent tendency. The RAPD assay, because of its efficacy to unmask alterations in genomic DNA induced by arsenic at low exposure level of 10 µg L(-1), appears to be a sensitive and potential tool for detecting arsenic genotoxicity.
砷是一种引起全球关注的地下水污染物。它是一种强效的人类致癌物，多项人体和动物研究报告了其显著的基因毒性作用。本研究调查了随机扩增多态性DNA（RAPD）分析法在研究低水平暴露于砷的金鱼（Carassius auratus）中DNA损伤效应方面的适用性。将四组实验鱼，A、B、C和D组，分别置于水族箱水中，连续15天暴露于0、10、50和1000 μg L(-1)的砷中。分别对每条鱼进行基因组DNA提取，随后进行RAPD聚合酶链反应扩增。在使用的33种引物中，一种任意的十聚体引物（PUZ-19）表现出最丰富的信息，并且能够在砷暴露和未暴露（对照）样本之间的RAPD图谱中呈现显著变化。引物PUZ-19在不同实验组中扩增出11个不同的位点，有四条清晰的多态性条带。在未暴露组中突出的X和XIII扩增位点，在砷暴露组中未出现。相反，I和XI RAPD条带在所有暴露组中作为新的扩增位点出现。然而，基因组DNA的这种变化并未呈现出明显的剂量依赖性趋势。RAPD分析法由于能够揭示在10 μg L(-1)的低暴露水平下砷诱导的基因组DNA变化，似乎是检测砷基因毒性的一种敏感且有潜力的工具。
