Molecular fingerprinting of some Mentha 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.