Abstract:
DNA studies of endangered or extinct species often rely on ancient or degraded remains. The majority of ancient DNA (aDNA) extraction protocols focus on skeletal elements, with skin and hair samples rarely explored. Similar to that found in bones and teeth, DNA extracted from historical or ancient skin and fur samples is also extremely fragmented with low endogenous content due to natural degradation processes. Thus, the development of effective DNA extraction methods is required for these materials. Here, we compared the performance of two DNA extraction protocols (commercial and custom laboratory aDNA methods) on hair and skin samples from decades-old museum specimens to Iron Age archaeological material. We found that apart from the impact sample-specific taphonomic and handling history has on the quantity and quality of DNA preservation, skin yielded more endogenous DNA than hair of the samples and protocols tested. While both methods recovered DNA from ancient soft tissue, the laboratory method performed better overall in terms of DNA yield and quality, which was primarily due to the poorer performance of the commercial binding buffer in recovering aDNA.
濒危或已灭绝动物的DNA研究通常依据古代或已严重降解的标本遗存。比较成熟的古DNA(ancient DNA,aDNA)提取方法主要针对于骨骼样本,对于皮张和毛发的研究较为少见。与古代的骨骼和牙齿情况相似,陈旧皮张样品中的DNA也由于自然降解等情况的存在,使得获取到的DNA片段长度极短、内源DNA含量极低。因此,针对这些样品,需要开发有效的DNA提取方法。本研究以几十年前到铁器时代的动物皮张和毛发样品为材料,比较2种提取方法(试剂盒法和古DNA实验室法)及相互组合的2种方法的DNA提取效果。研究发现除样品本身的差别(如年代等),皮张样品比毛发样品保留更多的内源DNA。所有方法都能够从陈旧的皮张样品中获取内源DNA,但是实验室的方法在DNA产量和质量上整体优于其它方法,实验室方法在纯化上的表现优于试剂盒方法。.