【摘要】 目的 以河南洛阳二里头遗址出土的距今3000多年的夏代人牙齿为标本，从口腔医学的角度分析牙齿DNA提取的污染控制，并进行PCR扩增条件的比较研究。方法 对古代人类牙齿样本进行去污处理，放入液氮研磨机中打磨成牙粉，使用GENECLEAN○R Kit for Ancient DNA 试剂盒从牙粉中提取DNA分子；利用不同条件的5种PCR反应体系扩增古DNA。结果 从牙齿样本中抽提出古代DNA片段A；在PCR扩增中，加入适量的小牛血清蛋白BSA有助于消除古代样本中PCR抑制物的作用；适合的Mg2+浓度则有助于增加DNA聚合酶的活性，减少非特异性扩增。结论 古DNA试剂盒是一种有效的古DNA抽提方法；小牛血清蛋白BSA和Mg2+浓度对PCR反应存在影响。

     【关键词】 古代人类牙齿；DNA；提取；扩增；小牛血清蛋白; Mg2+

    A study of extraction DNA from ancient teeth and the influences of amplifying conditions

    SHI Lin，ZENG Xiang-long.Peking University School and Hospital of Stomatology，Beijing 100081，China

    【Abstract】 Objective To extract DNA from human ancient teeth remains more than 3000-years-old excavated from Erlitou ruin in Henan province，and analyze the pollution control from dental aspect and study the influences of different conditions of PCR.Methods The teeth were cleaned and grinded into powder by FREEZER/MILL6750. DNA was extracted with ancient DNA extraction kit and amplified under 5 different polymerase chain reaction conditions.Results DNA was extracted from teeth powder; BSA helps to eliminate the effects of inhibitions; proper density of Mg2+ helps to increase the activity of TaqE and avoid the amplifying errors.Conclusion Ancient DNA extraction kit is a effective way to extract ancient DNA; BSA and the density of Mg2+ have influences on the results of PCR. ......