Table 2.

DNA methods for identification of Panax species

Techniques	Samples to differentiate	Prerequisite	Summary of results	Year of publication	Ref
PCR-RFLP	Six Panax species and adulterants	ITS1-5.8S-ITS2 sequences	The polymorphisms in the ITS1-5.8S-ITS2 sequence among the samples can be shown using various restriction enzymes to create species-specific RFLP profiles. Ten per cent of contamination of P. ginseng was detected from P. quinquefolius sample.	1999	14
PCR-RFLP	Three Panax species	18S sequences	Based on the 18S rRNA gene, three Panax species gave species-specific electrophoretic profiles by PCR-RFLP and expected fragments corresponding to each species were detected only under defined conditions by mutant allele specific amplification (MASA, i.e. ARMS) analyses.	1997	35
PCR-RFLP	P. ginseng from four localities, one from China and three from Korea	18S sequences	A ginseng sample showed fragments distinctive from the other two samples of the same country but different locality origins.	2001	36
AFLP	P. ginseng and P. quinquefolius	no	Polymorphic bands unique to P. ginseng and to P. quinquefolius and bands common to them were identified. P. ginseng samples from different farms in China and Korea are homogeneous genetically. P. quinquefolius from different sources are much more heterogeneous.	2002	42
RAPD	P. ginseng from four localities, one from China and three from Korea	no	Similarity among the DNA of ginseng plants analyzed was low.	2001	36
RAPD	Three strains of P. ginseng	no	A 725 bp band was present in the elite strain Aizu K-111 (now called Kaishusan) while the other strains did not always show this band.	2001	62
RAPD	Two cultivated groups of ginseng	no	Cluster analysis of the patterns showed that the genetic relationship between different strains of Da-maya group is closer than those strains of E-maya group.	2004	64
RAPD and AP-PCR	Three Panax species and adulterants	no	Fingerprints for P. ginseng or P. quinquefolius were basically consistent irrespective of plant source or age compared to the very different fingerprints from adulterants. The degree of similarity of the fingerprints confirmed that P. ginseng is more closely related to P. quinquefolius than it is to P. notoginseng.	1995	52
AP-PCR	Oriental ginseng from two sources and two American ginseng	no	Oriental ginseng from two sources produced nearly identical fingerprints. Two American ginseng samples gave fingerprints distinctive to the species with two primers tested but polymorphic and significantly different fingerprints with one of the primers tested. Therefore, the American ginseng samples were supposed to be from different strains.	1994	60
DALP	P. ginseng and P. quinquefolius	no	A DALP fragment was found present in all P. ginsengs but absent in all the P. quinquefolius examined. The species-specific band was converted to sequence-tagged site (i.e. amplification by specific primers giving a species-specific band) for quick authentication.	2001	95
DAMD	P. ginseng and P. quinquefolius	polymorphic AFLP band	A polymorphic AFLP band in P. ginseng contains a minisatellite which can be used in DAMD analysis to authenticate the two tested ginsengs.	2002	42
SCAR	Two Panax species and adulterants	polymorphic RAPD fragment	There is a 25 bp insertion in P. ginseng for a polymorphic RAPD fragment. By using primers designed based on this polymorphic fragment, P. quinquefolius and P. ginseng can be differentiated. Amplification on four other Panax species and two ginseng adulterants gave markedly different products.	2001	91
ARMS	Five Panax species and corresponding Ginseng drugs	trnK and nuclear 18S gene sequences	Five sets of species-specific primers with two pairs in each set were designed. Two expected fragments, one from trnK gene and another from 18S rRNA gene, were observed simultaneously only when the set of species-specific primers encountered template DNA of the corresponding species.	2004	121
SSR	Two Panax species	primer sequences for the loci	Using nine of the 16 screened loci, Chinese ginseng was differentiated unambiguously from the American samples. Some of the informative loci showed different allelic patterns among ginsengs from different farms.	2003	25
SSR	American ginseng and Oriental ginseng, cultivated and wild American ginseng	primer sequences for the loci	American ginseng had a different allele pattern (allele frequency in an American ginseng population of 34 cultivated and 21 wild ginseng) in two microsatellite loci compared with that of the Oriental ginseng (six from China and South Korea). Cultivated and wild American ginseng were distinguished.	2005	141
Sequencing	Three Panax species	primer sequences for 18S region	The sequences of the 18S rRNA region of 3 Panax species have different base substitutions at four nucleotide positions. By the polymorphism, the ginseng species from commercial samples were identified.	1996	186
Sequencing	Twelve Panax species	primer sequences for ITS and 5.8S regions	The sequences of the ITS and 5.8S coding region were used to reconstruct the phylogenetic relationships among twelve Panax species. P. quinquefolius was suggested to be more closely related to the eastern Asian species than P. trifolius. Previous suggestions about monophyly of P. ginseng, P. notoginseng and P. quinquefolius were not supported by the ITS data. Several biogeographical implications were inferred from the results.	1996	187
Sequencing	Panax notoginseng of different cultivar origins	primer sequences for 18S and matK genes	The nuclear 18S rRNA and chloroplast matK genes of 18 samples of Panax notoginseng and its processed material Sanqi (Radix Notoginseng) were found to be identical regardless of cultivar origin. Thus the same strain should be used in cultivation for conservation of the species.	2006	188
Sequencing	P. notoginseng and adulterants	primer sequences for 18S and matK genes	Notoginseng and its adulterants were differentiated on the basis of their sequence variation in the nuclear ribosomal RNA small subunit (18S rRNA) and chloroplast matK gene.	2001	67
Sequencing	Two Panax species and adulterants	primer sequences for ITS and rbcL genes	The nuclear ITS and chloroplast rbcL regions were amplified using universal primers and then sequenced using nested ginseng-specific primers. All the samples including five root samples, thirteen powder samples and six capsule samples were identified as American or Korean ginseng except a capsule and a tablet that were identified as soybean, by using the universal primers for sequencing. They could not be sequenced by the nested primers.	2000	174

The results obtained from Panax do not represent Chinese medicines. The results of specific techniques depend on their conditions (e.g. primers and magnesium concentration).