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

The genus Mentha is of particular economic importance. The development of new methods for the characterisation of Mentha species is crucial for their unequivocal identification. Amplification of the non-transcribed spacer (NTS) of the 5S-rRNA gene was used to characterise some Mentha species, which revealed a high-specific variability. Cloning and sequencing of all amplified NTS fragments enabled the discrimination among almost all species. In silico 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）具有重要的经济价值。开发薄荷属物种的新型鉴定表征方法，对实现其准确无歧义的物种鉴别至关重要。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鉴定表征分析，结果显示该区域存在较高的物种特异性变异。对所有扩增得到的NTS片段进行克隆与测序，可实现绝大多数薄荷属物种的有效区分。计算机模拟（in silico）与实验分析在扩增得到的5S-NTS区域中鉴定出特异性限制性酶切位点，借助聚合酶链式反应-限制性片段长度多态性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。