Ciavaglia Sherryn A, Tobe Shanan S, Donnellan Stephen C, Henry Julianne M, Linacre Adrian M T
Flinders University, Adelaide, South Australia, Australia; Forensic Science SA, Adelaide, South Australia, Australia.
Flinders University, Adelaide, South Australia, Australia.
Forensic Sci Int Genet. 2015 May;16:64-70. doi: 10.1016/j.fsigen.2014.12.002. Epub 2014 Dec 12.
Python snake species are often encountered in illegal activities and the question of species identity can be pertinent to such criminal investigations. Morphological identification of species of pythons can be confounded by many issues and molecular examination by DNA analysis can provide an alternative and objective means of identification. Our paper reports on the development and validation of a PCR primer pair that amplifies a segment of the mitochondrial cytochrome b gene that has been suggested previously as a good candidate locus for differentiating python species. We used this DNA region to perform species identification of pythons, even when the template DNA was of poor quality, as might be the case with forensic evidentiary items. Validation tests are presented to demonstrate the characteristics of the assay. Tests involved the cross-species amplification of this marker in non-target species, minimum amount of DNA template required, effects of degradation on product amplification and a blind trial to simulate a casework scenario that provided 100% correct identity. Our results demonstrate that this assay performs reliably and robustly on pythons and can be applied directly to forensic investigations where the presence of a species of python is in question.
蟒蛇物种经常出现在非法活动中，物种鉴定问题可能与这类刑事调查相关。蟒蛇物种的形态学鉴定可能会受到许多问题的困扰，而通过DNA分析进行分子检测可以提供一种替代的、客观的鉴定方法。我们的论文报道了一对PCR引物对的开发和验证，该引物对可扩增线粒体细胞色素b基因的一个片段，该片段先前已被认为是区分蟒蛇物种的一个良好候选基因座。我们使用这个DNA区域对蟒蛇进行物种鉴定，即使模板DNA质量很差，法医证据物品可能就是这种情况。本文展示了验证测试以证明该检测方法的特性。测试包括该标记物在非目标物种中的跨物种扩增、所需的最低DNA模板量、降解对产物扩增的影响以及一项模拟实际案件情况的盲测，该盲测提供了100%正确的鉴定结果。我们的结果表明，该检测方法在蟒蛇身上表现可靠且稳健，可直接应用于涉及蟒蛇物种存在问题的法医调查。
