古DNA：提取、特征分析、分子克隆及酶促扩增。

Department of Biochemistry, University of California, Berkeley 94720.

Proc Natl Acad Sci U S A. 1989 Mar;86(6):1939-43. doi: 10.1073/pnas.86.6.1939.

Several chemical and enzymatic properties were examined in the DNA extracted from dry remains of soft tissues that vary in age from 4 to 13,000 years and represent four species, including two extinct animals (the marsupial wolf and giant ground sloth). The DNA obtained was invariably of a low average molecular size and damaged by oxidative processes, which primarily manifest themselves as modifications of pyrimidines and sugar residues as well as baseless sites and intermolecular cross-links. This renders molecular cloning difficult. However, the polymerase chain reaction can be used to amplify and study short mitochondrial DNA sequences that are of anthropological and evolutionary significance. This opens up the prospect of performing diachronical studies of molecular evolutionary genetics.

对从年龄在4年至13000年不等的软组织干遗骸中提取的DNA进行了几种化学和酶学性质的检测，这些遗骸代表了四个物种，包括两种已灭绝动物（袋狼和巨型地懒）。所获得的DNA平均分子大小始终较低，并受到氧化过程的损伤，氧化过程主要表现为嘧啶和糖残基的修饰以及无碱基位点和分子间交联。这使得分子克隆变得困难。然而，聚合酶链反应可用于扩增和研究具有人类学和进化意义的短线粒体DNA序列。这为进行分子进化遗传学的历时性研究开辟了前景。