古DNA及其在生物系统与进化研究中的应用

古DNA是指从已经死亡的古代生物的遗体和遗迹中得到的DNA.本文回顾了近20年古DNA研究所经历的3个阶段,从早期参与研究的科学家较少并主要利用克隆技术,到后来由于PCR技术的出现以及提取化石DNA技术的成熟从而出现大量有关古DNA的报道;近几年由于发现不少问题,并引起激烈的争论,科学家们因此而开始考虑古DNA的真实性问题,并且提出了开展古DNA研究的严格标准.本文还讨论了古DNA在人类起源、系统发育重建、动植物驯化及考古研究中的重要意义以及现状,表明古DNA的研究给某些原先的观点如人类的非洲起源说提供了重要证据,也对某些观点提出了挑战;古DNA研究还提供了某些已经灭绝生物的形态学和分子资料,为从序列上确定古代材料的系统位置并有效地补充仅用现代DNA建立起来的谱系提供了来自古生物的依据.在动植物驯化及考古方面,古DNA证据也为科学家提供了许多有价值的信息.最后,本文还对古DNA研究的应用前景进行了展望.

Ancient DNA Study and its Progress in Systematic and Evolutionary Biology

Ancient DNA is DNA sequences extracted from ancient biological remains. This paper briefly reviews the 20-year history of ancient DNA study from its early period mainly with the technol- ogy of cloning to later use of PCR technology and the mature technology of extracting DNA from fossils. In the recent years, because of the emergence of many problems and fierce controversy in ancient DNA study, scientists began to consider the authenticity of ancient DNA and put forward some strict standards. Here, we discuss the significance and progress of ancient DNA studies involv- ing anthropology, systematic and evolutionary biology, biological domestication, and archeology. The data from ancient DNA studies provide additional evidence to support former viewpoints such as the out of Africa theory . In the study of systematics and evolution, study of ancient DNA added valuable information about extinct biological groups and facilitated the reconstruction of phyloge- netic relationships of organisms. Ancient DNA study also provided valuable insights into biological domestication and archeology of both domesticated animals and crop plants. Finally, perspectives and trends of ancient DNA study are reviewed.