Janczewski D N, Yuhki N, Gilbert D A, Jefferson G T, O'Brien S J
Biological Carcinogenesis and Development Program, Program Resources, Inc./DynCorp, Frederick, MD.
Proc Natl Acad Sci U S A. 1992 Oct 15;89(20):9769-73. doi: 10.1073/pnas.89.20.9769.
A method for the successful extraction of sequestered cellular DNA from 14,000-year-old fossil bones was developed and applied to asphalt-preserved specimens of the extinct saber-toothed cat, Smilodon fatalis. Two distinct gene segments, the mitochondrial gene for 12S rRNA and nuclear FLA-I (the feline class I major histocompatibility complex gene), from three different individual fossil specimens were cloned and sequenced after PCR amplification. Comparison of fossil-derived DNA sequences to homologous regions in 15 living carnivorous species, including 9 species of Felidae and 6 nonfelids, affirmed the phylogenetic placement of Smilodon within the modern radiation of Felidae distinct from the Miocene paleofelid (Nimravidae) saber-toothed "cat" species. These results raise the prospect of obtaining genetically informative DNA from preserved bones of extinct fossil species, particularly among the 2 million specimens excavated from the asphaltic sediments at Rancho La Brea in metropolitan Los Angeles.
一种从具有14000年历史的化石骨骼中成功提取封存细胞DNA的方法被开发出来，并应用于已灭绝的剑齿虎（致命刃齿虎）保存在沥青中的标本。在PCR扩增后，从三个不同个体的化石标本中克隆并测序了两个不同的基因片段，即线粒体12S rRNA基因和核FLA-I（猫科I类主要组织相容性复合体基因）。将化石衍生的DNA序列与15种现存食肉动物物种（包括9种猫科动物和6种非猫科动物）的同源区域进行比较，证实了剑齿虎在猫科现代谱系中的系统发育位置，与中新世古猫科（猎猫科）剑齿“猫”物种不同。这些结果为从已灭绝化石物种的保存骨骼中获取具有遗传信息的DNA带来了希望，特别是在从洛杉矶大都市兰乔拉布雷亚沥青沉积物中挖掘出的200万个标本中。
