Osentoski M F, Lamb T
Department of Biology, East Carolina University, Greenville, NC 27858, USA.
Mol Ecol. 1995 Dec;4(6):709-18. doi: 10.1111/j.1365-294x.1995.tb00271.x.
The slow rate of mtDNA evolution in turtles poses a limitation on the levels of intraspecific variation detectable by conventional restriction fragment surveys. We examined mtDNA variation in the gopher tortoise (Gopherus polyphemus) using an alternative restriction assay, one in which PCR-amplified segments of the mitochondrial genome were digested with tetranucleotide-site endonucleases. Restriction fragment polymorphisms representing four amplified regions were analysed to evaluate population genetic structure among 112 tortoises throughout the species' range. Thirty-six haplotypes were identified, and three major geographical assemblages (Eastern, Western, and Mid-Florida) were resolved by UPGMA and parsimony analyses. Eastern and Western assemblages abut near the Apalachicola drainage, whereas the Mid-Florida assemblage appears restricted to the Brooksville Ridge. The Eastern/Western assemblage boundary is remarkably congruent with phylogeographic profiles for eight additional species from the south-eastern U.S., representing both freshwater and terrestrial realms.
海龟线粒体DNA（mtDNA）进化速率缓慢，这限制了通过传统限制性片段分析所能检测到的种内变异水平。我们使用一种替代限制性分析方法，研究了地鼠龟（Gopherus polyphemus）的mtDNA变异，该方法是用四核苷酸位点内切酶消化线粒体基因组的PCR扩增片段。分析了代表四个扩增区域的限制性片段多态性，以评估该物种分布范围内112只乌龟的种群遗传结构。共鉴定出36种单倍型，并通过UPGMA和简约分析解析出三个主要地理组合（东部、西部和佛罗里达中部）。东部和西部组合在阿巴拉契科拉排水系统附近相邻，而佛罗里达中部组合似乎局限于布鲁克斯维尔岭。东部/西部组合边界与美国东南部另外八个物种的系统地理学概况非常一致，这些物种涵盖淡水和陆地领域。
