动物类中药DNA条形码鉴定研究进展

DNA基因鉴定是近年来应用在中药鉴定中较为重要的分子生物技术,该技术能够很好地从基因层面上鉴别药材,具有较高的准确性。DNA基因鉴定包括DNA分子遗传标记,核酸探针杂交,DNA条形码分子鉴定法等,其中发展最快的为DNA条形码分子鉴定法。DNA条形码分子鉴定法是利用基因组中一段公认的、相对较短的DNA序列来进行物种鉴定的一种分子生物学技术,是传统形态鉴别方法的有效补充。由于不同物种的DNA序列是由腺嘌呤(A),鸟嘌呤(G),胞嘧啶(C),胸腺嘧啶(T)4种碱基以不同顺序排列组成,因此对某一特定DNA片段序列进行分析即能够区分不同物种。Hebert等在2003年提出了通过测定线粒体细胞色素C氧化亚基I(COI)基因序列来鉴定动物的种类。陈士林等则在大量实验的基础上提出了鉴别动物的基因以COI基因为主,ITS2基因为辅的动物类药材DNA条形码鉴定体系。大量的实验表明,通过DNA条形码来鉴别动物具有准确性、可行性、简便性、通用性,为鉴别动物物种及发现新物种提供了新的方法,为鉴别动物药材的真伪提供了科学的依据。但由于该技术是通过基因进行鉴定,对实验材料及提取方法有较高要求,对一些年代较久的动物药材,其DNA降解较为严重,为DNA提取技术提出了较高的要求;该技术只能鉴别其来源是否准确却不能鉴别其药用部位是否准确,这就需要结合其他鉴别方法来准确鉴别其药用部位。本文通过综合国内外对DNA条形码的研究,为日后的研究和应用提供理论依据。

Advances in Animal Medicine DNA Barcoding

DNA gene identification is used as a more important molecular biological technology to identify traditional Chinese medicine in recent years. It can identify good herbs at the genetic level, with a high accuracy. DNA gene identification includes DNA molecule genetic markers, DNA hybridization and DNA barcoding molecular identification method, particularly the fastest growing one is DNA barcoding molecular identification method. DNA barcoding molecular identification method is a molecular biological technique to identify species using an admittedly short DNA sequence in genome, and an effective complement to traditional morphological identification methods. Because DNA sequences of different species were composed of four bases, namely adenine (A), guanine (G), cytosine (C) and thymine (T), analysis on a specific sequence of DNA fragments can distinguish different species. Hebert, proposed the animal species identification method by measuring mitochondrial cytochrome C oxidase subunit I (COI) gene sequences in 2003.CHEN Shi-lin proposed to identify genes with COI gene-dominated and ITS2 gene-supplemented animal medicine DNA barcoding system on the basis of a large number of experiments on animals. A large number of experiments have showed that, DNA barcoding is accurate, feasible, simple and general to identify animals, and provides a new method for identifying animal species, finding new species and authenticating animal medicines. However, because the technology is to identify by gene, it has higher requirements for experimental materials and extraction methods. Particularly, animal medicines prepared many years ago have a severe DNA degradation, which sets higher requirements for the DNA extraction technology. In this case, the technology can only identify the exact source, but not its medicinal parts, which has to be identified in the combination with other identification methods. In this article, studies on DNA barcodes at home and abroad are summarized to provide a theoretical basis for future studies and applications.