基于SNP位点鉴定砂仁药材物种

A Rapid SNP-based Identification Method for Distinguishing the Three Origins of Fructus Amomi

目的:为建立基于单核苷酸多态性(SNP)技术鉴别砂仁3个基原(阳春砂Amomum villosum、海南砂Amomum longiligulare、绿壳砂Amomum villosum var.xanthioides)的方法,对这3个种共计60份材料ITS2序列进行分析比较。方法:将实验所得砂仁ITS2序列,应用CodonCode Aligner软件进行序列拼接比对。用MEGA 5.0导出各序列变异位点,并对变异位点进行分析。为验证结果准确性,下载砂仁3个基原GenBank的所有ITS2序列,共计34条,对结果进行验证。结果:砂仁ITS2序列比对后长度为230 bp,3个不同基原在135 bp和199 bp处存在稳定SNP(s)变异位点。结论:本研究开发的两个稳定的SNP(s)位点可以快速准确地鉴定砂仁药材3个基原。

Medicinal plants of the Fructus Amomi containing three species （Amomum villosum, Am omum longiligu- lare, Amomum villosum var. xanthioides）are well-known, which are widely used as traditional medicines. The mor- phological characteristics of the three origins are very similar, especially in the form of seed. In this study, 60 sam- ples of Fructus Amomi were collected, and 34 sequences of the Fructus Amomi and their adulterants from GenBank were analyzed. Single nucleotide polymorphisms （SNPs） were detected. All the ITS2 sequences here （including our ex- periments and GenBank data）were examined for SNPs at the interspecies level. Results from the study revealed that two stable bases at position 135 bp and 199 bp were found, which could be used as a unique marker to distinguish the three origins of Fructus Amomi. The two SNPs in the ITS2 were found to exist stably between the three species, and all the GenBank sequences of the Fructus Amomi. Our findings indicated that SNP-based DNA barcoding could be used as an efficient method for the rapid and accurate identification of the three origins of Fructus Amomi.