Data from: Preservation of RNA and DNA from mammal samples under field conditions

Ecological and conservation genetics require sampling of organisms in the wild. Appropriate preservation of the collected samples, usually by cryostorage, is key to the quality of the genetic data obtained. Nevertheless, cryopreservation in the field to ensure RNA and DNA stability is not always possible. We compared several nucleic acid preservation solutions appropriate for field sampling and tested them on rat (Rattus rattus) blood, ear and tail tip, liver, brain and muscle. We compared the efficacy of a nucleic acid preservation (NAP) buffer for DNA preservation against 95% ethanol and Longmire buffer, and for RNA preservation against RNAlater (Qiagen) and Longmire buffer, under simulated field conditions. For DNA, the NAP buffer was slightly better than cryopreservation or 95% ethanol, but high molecular weight DNA was preserved in all conditions. The NAP buffer preserved RNA as well as RNAlater. Liver yielded the best RNA and DNA quantity and quality; thus, liver should be the tissue preferentially collected from euthanized animals. We also show that DNA persists in nonpreserved muscle tissue for at least 1 week at ambient temperature, although degradation is noticeable in a matter of hours. When cryopreservation is not possible, the NAP buffer is an economical alternative for RNA preservation at ambient temperature for at least 2 months and DNA preservation for at least 10 months.

生态学与保护遗传学研究需对野生生物进行采样。对采集样本的妥善保存——通常采用超低温保存（cryostorage）——是保障所获遗传数据质量的关键。然而，野外环境中为确保RNA与DNA稳定性而实施的超低温保存并非总能实现。我们对比了数种适配野外采样的核酸保存液，并以大鼠（黑家鼠，Rattus rattus）的血液、耳尖、尾尖、肝脏、脑组织及肌肉组织为样本开展测试。在模拟野外环境下，我们分别对比了核酸保存（NAP）缓冲液与95%乙醇、Longmire缓冲液对DNA的保存效果，以及其与RNAlater（Qiagen）、Longmire缓冲液对RNA的保存效果。结果表明，针对DNA保存，NAP缓冲液的效果略优于超低温保存或95%乙醇，且所有实验条件下均成功保留了高分子量DNA；NAP缓冲液对RNA的保存效果与RNAlater相当。肝脏样本的RNA与DNA产出量及质量均为最优，因此从安乐处死的动物体内采样时，应优先选取肝脏组织。此外我们证实，未添加保存液的肌肉组织在室温环境下，其DNA至少可留存1周，尽管数小时内即可观察到明显的DNA降解现象。当无法开展超低温保存时，NAP缓冲液是一种经济实用的替代方案，可在室温下至少实现RNA长达2个月的保存、DNA长达10个月的保存。