Servicio de Huellas Digitales Genéticas, School of Pharmacy and Biochemistry, Universidad de Buenos Aires, Buenos Aires, Argentina.
Forensic Sci Int Genet. 2013 Sep;7(5):488-93. doi: 10.1016/j.fsigen.2013.05.002. Epub 2013 Jun 28.
DNA genotyping techniques have been used successfully in forensic science for almost three decades and represent the gold standard for individual identification. However, efficient protocols for obtaining DNA from exhumed bones suitable for genotyping are still scarce and most of them require a considerable amount of starting material, are time consuming and are inefficient for reducing inhibitor's effects. We sought to develop an optimised protocol for extracting DNA from bone samples obtained from exhumations. We tested two approaches for preparing bone samples: (a) fine powder and (b) thin slices of bone. The best ratio of bone amount to DNA yields was assessed by a titration experiment using bone powder ranging from 50 to 1000mg. We obtained optimal DNA yields (27pg mg(-1) on average) when 150-200mg of starting material were processed using a one-step demineralisation method. Better-quality profiles (determined by the number of genotyped loci) were obtained when DNA was extracted from bone slices compared to extraction from bone powder. From bone slices 83.9% and from bone powder 46.7% of the samples provided genotypes for 11 or more loci. Since bone preparation procedures were carried out at room temperature, the method developed in the present study might be an attractive alternative to the standard freeze-mill approach, being faster and more cost-efficient.
DNA 基因分型技术在法医学中已经成功应用了近三十年，是个体识别的金标准。然而，从挖掘出的骨骼中获取适合基因分型的高效 DNA 方案仍然很少，而且大多数方案需要相当数量的起始材料，耗时且对抑制剂的效果效率低下。我们试图开发一种从挖掘出的骨骼样本中提取 DNA 的优化方案。我们测试了两种制备骨骼样本的方法：（a）细粉末和（b）薄骨片。通过使用 50 至 1000mg 的骨粉进行滴定实验来评估最佳的骨量与 DNA 产量比。当使用一步脱矿化方法处理 150-200mg 的起始材料时，我们获得了最佳的 DNA 产量（平均 27pg mg(-1)）。与从骨粉中提取相比，从骨片中提取的 DNA 得到了更好的图谱（通过基因分型位点数确定）。从骨片中，83.9%的样本和从骨粉中，46.7%的样本提供了 11 个或更多基因座的基因型。由于骨骼制备程序是在室温下进行的，因此本研究中开发的方法可能是标准冷冻研磨方法的一种有吸引力的替代方法，速度更快，成本效益更高。
