Molecular fingerprinting of some <i>Mentha</i> species by sequencing and RFLP analysis of the 5S-rRNA non-transcribed spacer region

The genus <i>Mentha</i> is of particular economic importance. The development of new methods for the characterisation of <i>Mentha</i> species is crucial for their unequivocal identification. Amplification of the non-transcribed spacer (NTS) of the 5S-rRNA gene was used to characterise some <i>Mentha</i> species, which revealed a high-specific variability. Cloning and sequencing of all amplified NTS fragments enabled the discrimination among almost all species. <i>In silico</i> and experimental analyses identified specific restriction sites on the amplified 5S-NTS regions, facilitating the rapid and unambiguous discrimination of all the different species by polymerase chain reaction–restriction fragment length polymorphism. A direct comparison between essential oil composition and DNA fingerprinting confirmed a relationship between chemical and molecular data.薄荷属（Mentha）具有尤为重要的经济价值。开发针对薄荷属物种的表征新方法，对其无歧义鉴定至关重要。研究人员通过扩增5S核糖体RNA基因（5S-rRNA gene）的非转录间隔区（non-transcribed spacer, NTS），对部分薄荷属物种开展了表征研究，结果发现该区域存在高度的物种特异性变异。对所有扩增得到的NTS片段进行克隆与测序，可实现对绝大多数物种的区分鉴定。计算机模拟（in silico）与实验分析均在扩增得到的5S-NTS区域中鉴定出特异性酶切位点，借助聚合酶链式反应-限制性片段长度多态性（polymerase chain reaction–restriction fragment length polymorphism）技术，即可快速且无歧义地区分所有不同的薄荷属物种。对精油成分与DNA指纹图谱的直接比较分析，证实了化学数据与分子数据之间存在显著相关性。