Higgins Denice, Kaidonis John, Townsend Grant, Austin Jeremy J
Australian Centre for Ancient DNA, School of Earth and Environmental Sciences and Environment Institute, University of Adelaide, North Terrace, Adelaide, SA, 5005, Australia,
Forensic Sci Med Pathol. 2014 Mar;10(1):56-61. doi: 10.1007/s12024-013-9519-2. Epub 2014 Jan 8.
Teeth and bones are frequently used in the genetic analysis of degraded and ancient human and animal remains. Standard extraction methods, including most commercially available systems, may not yield sufficient DNA to enable successful genetic analysis. Addition of a carrier molecule and demineralization (via EDTA) can increase yields from samples containing limited amounts of DNA. However the benefits of carrier molecules have not been demonstrated for bones and teeth and demineralization introduces large reagent volumes that are difficult to integrate into commercial DNA extraction systems.
We compared nuclear DNA yields recovered from small samples of partially decomposed human teeth using a commercial silica-based DNA extraction system with and without the addition of carrier RNA and/or a low-volume demineralization step.
DNA yield was significantly improved with demineralization, but there was no significant effect of carrier RNA. The DNA content of a sample did not influence the significance of the effect of demineralization.
Using a simple low-volume (1 mL) demineralization step, prior to DNA extraction with the QIAmp DNA Investigator kit (Qiagen), as little as 50 mg of tooth powder can yield more than 500 ng of nuclear DNA.
牙齿和骨骼常用于降解的古代人类和动物遗骸的遗传分析。包括大多数市售系统在内的标准提取方法可能无法产生足够的DNA以实现成功的遗传分析。添加载体分子和脱矿质作用（通过乙二胺四乙酸）可以提高有限DNA含量样本的产量。然而，载体分子对骨骼和牙齿的益处尚未得到证实，且脱矿质作用会引入大量难以整合到商业DNA提取系统中的试剂。
我们使用基于硅胶的商业DNA提取系统，比较了在添加和不添加载体RNA及/或进行小体积脱矿质步骤的情况下，从部分分解的人类小牙齿样本中回收的核DNA产量。
脱矿质作用显著提高了DNA产量，但载体RNA没有显著影响。样本的DNA含量不影响脱矿质作用效果的显著性。
在使用QIAmp DNA Investigator试剂盒（Qiagen）进行DNA提取之前，采用简单的小体积（1 mL）脱矿质步骤，仅50毫克牙粉就能产生超过500纳克的核DNA。
