This Guidelines is applicable to authentication of Chinese Materia Medica (crude drug and some decoction pieces) and origin at species.

As an effective method to complement with traditional morphology-based approaches, molecular DNA barcoding refers to a molecular biological technique for species identification using a commonly recognized, relatively short DNA sequences of the genome. The DNA sequences of various species are composed of four repeating nucleotide bases adenine (A), guanine (G), cytosine (C), and thymine (T) in unique orders. Therefore, a specific DNA sequence of one species could be used to discriminate it from other species.

Molecular DNA barcoding of Chinese Materia Medica refers to a methodological system to identify Chinese Materia Medica through the second internal transcribed spacer of nuclear ribosomal DNA (ITS2)^① as the main barcode sequence for identification. With ITS2/ITS as the main sequence, psbA-trnH^② of chloroplast can be used as the complementary sequence for identification of herbal Chinese Materia Medica. For identification of Chinese Materia Medica from animal origin, Cytochrome C oxidase subunitⅠ(COI)^③ is used as the main sequence and ITS2 is used as the complementary sequence.