Abstract

The mitochondrial cytochrome oxidase c subunit 1 (COI) gene has been widely used in phylogenetic studies of crustaceans and analyses in population genetics. As COI studies have become more popular, there has been an increase in the number of reports of the presence of nuclear insertions of mitochondrial DNA (Numts) and mitochondrial heteroplasmy. Here, we provide evidence of both types of event in the COI sequences of Macrobrachium amazonicum, an economically important freshwater prawn, which is widespread in South America. Heteroplasmy and Numts were confirmed by different methods of DNA extraction (genomic, mitochondrial, and nuclear-enriched DNA), cloning, and sequencing, and were observed in 11 of the 14 populations sampled, primarily in the Amazon region. We discuss how the occurrence of these events affects the interpretation of the genetic relationships among the M. amazonicum populations, and we recommend caution when using COI for genetic inferences in prawns of the genus Macrobrachium, and in particular that any analysis should include nuclear markers.

摘要

线粒体细胞色素氧化酶c亚基1（COI）基因已被广泛用于甲壳类的系统发育研究和种群遗传学分析。随着COI研究变得越来越流行，关于线粒体DNA（Numts）核插入和线粒体异质性存在的报道数量也越来越多。在这里，我们提供了亚马逊沼虾COI序列中两种事件类型的证据。，一种在经济上很重要的淡水虾，在南美很普遍。通过不同的DNA提取方法（基因组，线粒体和富核DNA），克隆和测序证实了异质性和Numts，并在抽样的14个人群中的11个人群中观察到了这些，主要在亚马逊地区。我们讨论了这些事件的发生如何影响亚马逊分枝杆菌种群之间遗传关系的解释，并建议在使用COI进行Macrobrachium虾对虾的遗传推断时要特别小心，尤其是任何分析都应包括核标记。