Molecular identification of Ammodytes (PISCES, Ammodytidae) larvae, with ontogenetic evidence on separating populations

A total of ten larval Ammodytes were collected from the Yellow (5 specimens) and Bering Seas (5), and a 638 base pair sequence from their mitochondrial DNA COI genes was analyzed for species identification. Sequences were compared with those of adult Ammodytes personatus from the East (4), the Yellow (2) and the East China Seas (2), and Japan (3). Average genetic distance was 0.064 between the Yellow Sea larvae and the Bering Sea larvae, but was 0.0043 between the Yellow Sea larvae and all the adult A. personatus except two individuals from the East Sea. NJ-tree showed that five Yellow Sea larvae were closely clustered with adult A. personatus, except for two individuals. The five Bering Sea larvae were located distantly from adult A. personatus, and are thought to be A. hexapterus. We found morphological differences among two populations of A. personatus larvae and A. hexapterus larvae in morphometric characters and pigmentation. Our results indicated that the East Sea population of A. personatus is closer to A. hexapterus than to the Yellow Sea population of A. personatus, suggesting the East Sea population may be part of separate species.     

Gene Flow between the Korean Peninsula and Its Neighboring Countries

SNP markers provide the primary data for population structure analysis. In this study, we employed whole-genome autosomal SNPs as a marker set (54,836 SNP markers) and tested their possible effects on genetic ancestry using 320 subjects covering 24 regional groups including Northern ( = 16) and Southern ( = 3) Asians, Amerindians ( = 1), and four HapMap populations (YRI, CEU, JPT, and CHB). Additionally, we evaluated the effectiveness and robustness of 50K autosomal SNPs with various clustering methods, along with their dependencies on recombination hotspots (RH), linkage disequilibrium (LD), missing calls and regional specific markers. The RH- and LD-free multi-dimensional scaling (MDS) method showed a broad picture of human migration from Africa to North-East Asia on our genome map, supporting results from previous haploid DNA studies. Of the Asian groups, the East Asian group showed greater differentiation than the Northern and Southern Asian groups with respect to Fst statistics. By extension, the analysis of monomorphic markers implied that nine out of ten historical regions in South Korea, and Tokyo in Japan, showed signs of genetic drift caused by the later settlement of East Asia (South Korea, Japan and China), while Gyeongju in South East Korea showed signs of the earliest settlement in East Asia. In the genome map, the gene flow to the Korean Peninsula from its neighboring countries indicated that some genetic signals from Northern populations such as the Siberians and Mongolians still remain in the South East and West regions, while few signals remain from the early Southern lineages.     

Molecular and morphological differences between two geographic populations of Salanx ariakensis (Salangidae) from Korea and Japan

Geographic variations of a salangid, Salanx ariakensis, from Korea and Japan, based on partial mtDNA cyt b gene sequences and morphometric data, are presented and compared with Salanx cuvieri from China. Analyses of molecular variance (AMOVA) suggested that the two populations of S. ariakensis differed significantly from each other in pairwise fixation index (F _ST = 0.43), although their reciprocal monophyly was not constructed in the phylogenetic analysis. The phylogenetic analysis, however, supported the reciprocal monophyly of S. ariakensis (Korean population + Japanese population) and S. cuvieri. Differences in genetic structure between the two populations of S. ariakensis were suggested by diversity indices, mismatch distribution shape, and minimum spanning network. In particular, diversity indices indicated that the Korean population was historically larger and more stable than the Japanese population. In addition, both the principal component analysis (PCA) and canonical discriminant analysis (CDA) for morphometric characters, and the Kruskal–Wallis test for some meristic characters, showed that the two populations of S. ariakensis differed from each other, although morphological differences between the two populations of S. ariakensis were smaller than those between S. ariakensis and S. cuvieri. Such morphological differences were consistent with the differences in mtDNA.     

Genetic divergence between the South Korean and Mongolian populations of the dung beetle,Gymnopleurus mopsus (Coleoptera: Scarabaeidae) based on mitochondrial cytochrome c oxidase subunit I (COI) gene sequences

The locally extinct dung beetle, Gymnopleurus mopsus Pallas, 1781 (Coleoptera: Scarabaeidae), has not been found in South Korea since the 1970s. This research was conducted to understand the genetic divergence between the South Korean and Mongolian populations of G. mopsus as a part of its reintroduction program in South Korea. The genetic distance and diversity were determined using the mitochondrial cytochrome c oxidase subunit I (COI) gene sequence (658 bp ) corresponding to the DNA barcode region. The mitochondrial COI gene sequences of 64 individuals of G. mopsus collected in South Korea (7 individuals) and Mongolia (57 individuals) showed a relatively high level of genetic diversity (nucleotide diversity, 0.0078 ± 0.0007; Haplotype diversity, 0.965 ± 0.017). The genetic distances between the South Korean and Mongolian populations lay within the intraspecific level and the phylogenetic reconstruction using the neighbor‐joining (NJ) method showed that all individuals belonged to a single clade. This result indicates that the current Mongolian population of G. mopsus is a good candidate source population to restore the locally extinct population of the species in South Korea.     

Distribution and genetic characteristics of Ephoron shigae (Ephemeroptera: Polymitarcyidae) in Korea

Ephoron shigae is distributed in Far East Russia, Korea and Japan, where it inhabits rivers, streams and lakes. Although this mayfly is a geographically parthenogenetic species, unisex populations have been observed only in Japan. We aimed to answer the following three questions: (i) whether there is a unisex population of E. shigae in Korea; (ii) whether migration and gene flow exists between E. shigae populations in Korea and Japan; and (3) whether E. shigae populations are fragmented in Korea because of mountains running to the north and south. We observed 20 populations across Korea and investigated the sex ratio in 12 populations. Our results showed that all the populations were bisex, and we believe that there is no unisex population of E. shigae in Korea. In addition, we examined the genetic structure of E. shigae in Korea by using the COI gene. The results showed that the Korean populations were clearly divergent from the Japanese populations; the level of genetic distance between the Korean and Japanese populations was interspecific rather than intraspecific. Therefore, parthenogenetic populations of E. shigae probably belong to unisex populations that originated in Japan, while the individuals would have not migrated to Korea. The Korean populations did not show clear fragmentation by geographic barrier, although this mayfly with extremely short adult stage (up to 2 h) could be a comparatively strong disperser across Korea.     

Genetic diversity and structure analyses on the natural populations of diploids and triploids of tiger lily, <Emphasis Type="Italic">Lilium lancifolium</Emphasis> Thunb., from Korea,China, and Japan

Tiger lily, Lilium lancifolium Thumb. is an endemic species in Korea. Genetic structure and diversity of diploid and triploid tiger lily accessions were analyzed using SSRP and IRAP molecular markers. All genetic indices analyzed showed that the diploids hold higher genetic variations compared to the triploids which were collected from Korea, China, and Japan. All variations found in triploids were also found in diploids to support the autotriploidy of L. lancifolium. It was also revealed that the triploid populations have experienced population regrowth from small population after population bottleneck. The population and phylogenetic analyses showed that analyzed tiger lilies were partitioned into three populations, Pop 1 from West Sea of Korean Peninsula, Pop 2 from South Sea of Korean Peninsula and Pop 3 of triploids in which many accessions of West Sea and South Sea were admixed in each partitioned group. Although the level of population differentiation is not extensive, F_ST analysis revealed some level of differentiation among the three populations. The analyses of genetic structure and phylogenetic dendrogram revealed admixture in some accessions among populations. All the results obtained in our analyses imply that autotriploid tiger lilies were originated from a small number of accessions of diploid L. lancifolium.     

Genetic population structure of the Fire-bellied toad <Emphasis Type="Italic">Bombina bombina</Emphasis> in an area of high population density: implications for conservation

In this study, we report the genetic population structure of the Fire-bellied toad Bombina bombina in Brandenburg (East Germany) in the context of conservation. We analysed 298 samples originating from 11 populations in Brandenburg using mitochondrial control region sequences and six polymorphic microsatellite loci. For comparison, we included one population each from Poland and Ukraine into our analysis. Within Brandenburg, we detected a moderate variability in the mitochondrial control region (19 different haplotypes) and at microsatellite loci (9–12 alleles per locus). These polymorphisms revealed a clear population structure among toads in Brandenburg, despite a relatively high overall population density and the moderate size of single populations (100–2000 individuals). The overall genetic population structure is consistent with a postglacial colonization from South East-Europe and a subsequent population expansion. Based on genetic connectivity, we infer Management Units (MUs) as targets for conservation. Our genetic survey identified MUs, within which human infrastructure is currently preventing any genetic exchange. We also detect an unintentional translocation from South East to North West Brandenburg, presumably in the course of fish stocking activities. Provided suitable conservation measures are taken, Brandenburg should continue to harbor large populations of this critically endangered species.     

Genetic status of Asiatic black bear (Ursus thibetanus) reintroduced into South Korea based on mitochondrial DNA and microsatellite loci analysis

The Asiatic black bear is one of the most endangered mammals in South Korea owing to population declines resulting from human exploitation and habitat fragmentation. To restore the black bear population in South Korea, 27 bear cubs from North Korea and Russian Far East (Primorsky Krai) were imported and released into Jirisan National Park, a reservoir of the largest wild population in South Korea, in 2004. To monitor the success of this reintroduction, the genetic diversity and population structure of the reintroduced black bears were measured using both mitochondrial and nuclear DNA markers. Mitochondrial D-loop region DNA sequences (615 bp) of 43 Japanese black bears from previous study and 14 Southeast Asian black bears in this study were employed to obtain phylogenetic inference of the reintroduced black bears. The mitochondrial phylogeny indicated Asiatic black bear populations from Russian Far East and North Korea form a single evolutionary unit distinct from populations from Japan and Southeast Asia. Mean expected heterozygosity (H(E)) across 16 microsatellite loci was 0.648 for Russian and 0.676 for North Korean populations. There was a moderate but significant level of microsatellite differentiation (F(ST) = 0.063) between black bears from the 2 source areas. In addition, genetic evidences revealed that 2 populations are represented as diverging groups, with lingering genetic admixture among individuals of 2 source populations. Relatedness analysis based on genetic markers indicated several discrepancies with the pedigree records. Implication of the phylogenetic and genetic evidences on long-term management of Asiatic black bears in South Korea is discussed.     

Intraspecific genetic polymorphism of Russian sturgeon <Emphasis Type="Italic">Acipenser gueldenstaedtii</Emphasis>

Three populations (Azov, Caspian, and Black Sea) of Russian sturgeon Acipenser queldenstaedtii were tested for polymorphism at nuclear (RAPD and microsatellites) and mitochondrial (PCR identification of two mitotypes) markers. In addition, morphometric analysis of he representatives of Azov population was carried out. According to the morphological characters, the Black Sea population occupied an intermediate position between the Caspian and Azov populations, reflecting the phylogeography of this species. In agreement with the morphometric data, genetic distances (the data of STR analysis) also placed the Black Sea population between the Caspian and Azov populations (F _ST = 0.058 and 0.043). The genetic distance between the Azov and Caspian population was somewhat higher (F _ST = 0.070). The highest allelic polymorphism at four microsatellite loci was found observed in Caspian population, while the lowest polymorphism was in the Sea of Azov. RAPD analysis distinguished high polymorphism within the populations, although it was not feasible for interpopulation analysis. Using the method differentiating the “baerii-like” and typical “gueldenstaedtii” mitotypes, the absence of the “baerii-like” marker in the Black Sea population was demonstrated. The frequency of this marker in Caspian and Azov populations constituted 31.1 and 1.8%, respectively. Possible evolutionary reasons for the interpopulation differences observed are discussed.     

Population genetic structure of the melon fly, <Emphasis Type="Italic">Bactrocera cucurbitae</Emphasis> (Diptera: Tephritidae), from China and Southeast Asia

The melon fly, Bactrocera cucurbitae Coquillett, is a species of fruit flies of significant agricultural interest. Of supposed Indian origin, the melon fly is now widely distributed throughout South East Asia up to China, while it has been recently eradicated from Japan. The population structure of seven geographic populations from coastal China, as well as samples from other regions of South East Asia and Japan, including lab colonies, have been studied using a 782 bp fragment of mitochondrial cytochrome oxidase I (COI) gene sequence. The observed genetic diversity was exceedingly low, considering the geographic scale of the sampling, and one single haplotype was found to be predominant from Sri Lanka to China. We confirm that Bactrocera cucurbitae exists in South East Asia as a single phyletic lineage, that Chinese populations are genetically uniform, and that no apparent genetic differentiation exists between these and three available Japanese melon fly sequences.     

Population Genetic Structure of the Endangered <Emphasis Type="Italic">Brasenia schreberi</Emphasis> in South Korea Based on Nuclear Ribosomal Spacer and Chloroplast DNA Sequences

Genetic variation of nuclear ribosomal ITS (nrITS) and chloroplast DNA (cpDNA) regions was investigated in Brasenia schreberi (Cabombaceae) to assess the population structure and to infer the evolutionary relationship among 12 populations distributed in South Korea. The combined sequence of the two regions was aligned to 2,069 bp, of which 28 sites were variable. In total, 20 genotypes were identified from 240 individuals of B. schreberi. Genotype diversity (Gd) and nucleotide diversity (Pi) on Jeju Island (Gd = 0.2511, Pi = 0.00012) were higher than those of the mainland of South Korea (Gd = 0.1358, Pi = 0.00005). The relatively low level of genetic variation of the mainland populations is associated with its higher genetic differentiation (G _ST = 0.095 on mainland and 0.039 on Jeju Island) and human activities. Minimum spanning network analysis demonstrated that the investigated populations of B. schreberi were subdivided into two geographical groups: the mainland of South Korea and Jeju Island. In addition, analysis of molecular variation showed that a large proportion (73.55%) of genetic differentiation existed between the two regions. These results strongly suggest the presence of significant barriers to gene flow between regions. Thus, the management unit for B. schreberi should be carefully designed to avoid the potential risk that can results from the admixture of individuals from the mainland and Jeju Island regions.     

Upwelling and eddies affect connectivity among local populations of the goldeye rockfish,Sebastes thompsoni (Pisces,Scorpaenoidei)

The goldeye rockfish, Sebastes thompsoni, commercial rockfish catch in the Northwest Pacific Ocean, may influence its population structure. To clarify the population genetic structure of Korean S. thompsoni and its degree of hybridization with the most close species, Sebastes joyneri, we analyzed a mitochondrial (mt) DNA control region and eleven polymorphic microsatellite (ms) loci. S. joyneri individuals were clearly distinguished from S. thompsoni by the mtDNA control region and ms loci results, with single interspecific hybridization between two species suggesting no impact on genetic structure of S. thompsoni. Analysis of mtDNA revealed no population structure within S. thompsoni, suggesting the survival of a single population in southern refugia during the glacial period. The ms loci results, in contrast, showed two genetically distinct clusters within S. thompsoni: One was predominant throughout Korean coasts (from the Yellow Sea, via the Korea Strait to the East Sea); the other was predominant at Dokdo Island in the East Sea; and both occurred in similar ratios at Wangdolcho Reef in the East Sea. A possible factor that restricts gene flow between Korean coastal and offshore populations in the East Sea may be related to the complex oceanic current patterns such as eddies and upwelling, which represent impermeable barriers to population connectivity for this species. Our findings highlight that these two populations might be representative of two separate stock within Korean waters and maintain their geographically related genetic structure.     

Population structure of the sailfin sandfish, Arctoscopus japonicus (Trichodontidae), in the Sea of Japan

We analyzed patterns of genetic diversity in the sailfin sandfish (Arctoscopus japonicus), focusing on population subdivisions within the Sea of Japan. We observed 270 specimens from nine sampling sites in 1999–2000, i.e., seven sites in the Sea of Japan and two sites from the Pacific coast of Hokkaido. An additional site (30 specimens) was sampled from eastern Korea in the spawning season of 2004 for comparison. Forty haplotypes, compiled into three haplogroups (A–C), were detected based on the comparison of a 400-bp sequence of the anterior part of the mitochondrial control region. In accordance with previous hypotheses from morphological and molecular analyses, genetic discontinuity between the Sea of Japan and the Pacific coast of Hokkaido was conspicuous. Within the Sea of Japan, eight sampling sites were not genetically uniform, and most of the variations among sites were detected between eastern Korea [the “eastern Korea” (EK) population: distributed from the Korean Peninsula to Mishima, Yamaguchi Prefecture] and the other sites along the coast of Japan [the “western Japan” (WJ) population: from Oki Islands to western Hokkaido] (Φ _CT  = 0.096, P = 0.0183). The WJ population, having lower genetic variability, showed significant departure from neutrality, indicating influences through a recent population expansion. The period of the expansion can be estimated to have begun on the order of 10⁴ years ago. We consider that the present Japan Sea populations have been formed through the invasion of a small ancestral stock to the Sea of Japan and its population expansion during the last glacial period or later. On the other hand, we failed to detect distinct evidence of a population expansion in the EK population. Haplogroup C, detected in a high frequency in this population, was estimated to have mixed with haplogroup A after rapid differentiations of the latter. Therefore, the EK population, strongly influenced by such a mixture, might possess haplogroup C in a higher frequency and a different haplotype composition from the WJ population.     

Molecular evidence for the taxonomic identity of Korean Adonis (Ranunculaceae)

 Although Korean Adonis has been traditionally recognized as Adonis amurensis Regel and Radde with various infraspecific taxa described, its taxonomic identity is still in dispute. We investigated the genetic variation in 60 individuals from 12 populations in Korea to elucidate the taxonomic identity of the Korean Adonis complex. Random amplified polymorphic DNA (RAPD) analysis revealed that Korean Adonis comprises three species: A. amurensis, A. pseudoamurensis, and A. multiflora. Adonis amurensis is distributed in northern central inland regions of Korea and A. pseudoamurensis is found in southern parts of the Korean peninsula. Adonis multiflora grows only on Cheju Island, which is the southernmost part of Korea. Phylogenetic analysis of nuclear ribosomal internal transcribed spacer (ITS) sequences partially supported the presence of three Adonis taxa in Korea as detected by RAPD analysis. The Adonis population on Jangbong Island located in the West Sea, which was referred to as A. pseudoamurensis on the basis of morphological examination, was separated from the other populations of A. pseudoamurensis. Otherwise, the molecular evidence is well congruent with the recent morphological study that proposes that Korean Adonis consists of these three species. Received: November 6, 2001 / Accepted: February 26, 2002     

Genetic variation of coreoleuciscus splendidus populations (Teleostei; Cypriniformes) from four major river drainage systems in South Korea as assessed by AFLP markers

Amplified fragment length polymorphism (AFLP) technique was used to assess genetic variation and population structuring of Coreoleuciscus splendidus (Teleostei; Cypriniformes) from four major river drainage systems in South Korea (i.e. the Han and Geum Rivers belonging to the West Korea Subdistrict and the Seomjin and Nakdong Rivers belonging to the South Korea Subdistrict). Four combinations of selective primers generated 152–186 DNA fragments, of which 45–59 were polymorphic. The Geum River population had the lowest genetic variation in terms of average heterozygosity. The pairwise genetic differentiation (F _ST) estimates showed that the four populations of C. splendidus were genetically differentiated (P < 0.05). The F _ST values were higher between population groups of the West and South Subdistricts than between populations from the two river systems within each subdistrict. A dendrogram based on the distance matrix revealed that all C. splendidus individuals bifurcated into two subdistrict population groups and were further divided into two river populations within each subdistrict. Individuals from each population consistently clustered together with high statistical support. The analysis of molecular variance after partitioning of C. splendidus populations into two groups (i.e. the West and South Korea Subdistricts) revealed very strong geographic structuring between them with 74.01% of total variance (P < 0.001). Taken together, the AFLP markers clearly distinguished not only between two population groups of the West and South Subdistricts but also between populations from two river systems within each subdistrict. Morphological differences between the two subdistrict population groups in body color and the presence of black array(s) on dorsal, anal, and caudal fin rays agreed with their high degree of genetic variation. Our findings strongly indicate that restricted dispersal and gene flow are apparent among four geographically separate populations of C. splendidus, and each population should be treated as an evolutionarily significant unit; this should be an a priori consideration for developing their conservation strategies.     

Genetic diversity and population structure of<Emphasis Type="Italic">Kalopanax pictus</Emphasis> (Araliaceae)

Kalopanax pictus (Araliaceae) is a long-lived woody species primarily distributed throughout East Asia. This species is regarded as medically and ecologically important in Korea. We used starch gel electrophoresis to investigate its allozyme variation and genetic structure in samples from Korean populations (both natural and cultivated). Our analysis of 10 enzymes revealed 18 loci, of which 10 were polymorphic (35.6%). Genetic diversity at the species and population levels were 0.200 and 0.149, respectively, with the mean for cultivated populations (0.124) being lower than for natural (wild) populations (0.181). Asexual and sexual reproduction modes, perennial habitat, and longevity all were possible factors contributing to such high diversity. An indirect estimate of the number of migrants per generation (N _m = 1.08) indicated that gene flow was not extensive among these Korean populations. Therefore, we suggest that geographical distance as well as reproductive isolation between wild and cultivated plants may play roles in shaping the population structure of this species.     

Genetic variation of <Emphasis Type="Italic">Picea jezoensis</Emphasis> populations in South Korea revealed by chloroplast,mitochondrial and nuclear DNA markers

Genetic variation associated with Picea jezoensis populations of South Korea was investigated using chloroplast (cp), mitochondrial (mt) and nuclear DNA markers. In South Korea, P. jezoensis is distributed across a very restricted area, being found on the summits of three mountains: Mts. Jiri, Dokyu and Gyebang. Examination of five region restriction enzyme combinations for mtDNA and four for cpDNA revealed haplotypes endemic to South Korea. The Gyebang population, the most northerly and most isolated, was genetically distinct from the other populations. Nuclear microsatellite markers indicated, overall, a low level of genetic diversity (H _e = 0.406) in South Korea; this could be attributed to genetic drift and/or founder effects associated with historical events. The Wilcoxon sign-rank test did not indicate a recent bottleneck in any of the populations irrespective of the model considered (infinite allele model, two-phased model of mutation, and stepwise mutation model). Microsatellite markers also demonstrated that the Gyebang population was distinct from the others. The results of this study could be used as the basis for conservation guidelines for the management of this species in South Korea.     

Genetic diversity and genetic structure of the endangered Manchurian trout, <Emphasis Type="Italic">Brachymystax lenok tsinlingensis</Emphasis>, at its southern range margin: conservation implications for future restoration

The Manchurian trout, Brachymystax lenok tsinlingensis (family: Salmonidae), is a cold freshwater fish endemic to Northeast Asia. South Korean populations of this species, which comprise its southern range limit, have recently decreased markedly in size and are now becoming critically endangered. We assessed the current population status of this species in South Korea by estimating the levels of genetic diversity and genetic structure of five natural and four restored populations using mitochondrial DNA (mtDNA) control region sequences and eight nuclear microsatellite loci. Levels of within-population genetic diversity were low, suggesting that past effective population sizes (N _e) have been small. Each population had one or a maximum of two mtDNA haplotypes. Microsatellite allelic richness (AR) was significantly higher for natural populations (mean AR?=?3.51; 95% confidence interval, 3.00–4.03) than for restored populations (mean AR?=?2.61; 2.38–2.98). South Korean populations were significantly genetically isolated from one another, with private mtDNA haplotypes and microsatellite alleles, suggesting that limited gene flow has been occurring among populations. A mtDNA phylogeny revealed that South Korean lineages were more closely related to those of China than to those of North Korea and Russia. Overall, we suggest that future restoration efforts aimed at South Korean populations should consider the genetic characteristics reported here, which should help to fulfil effective conservation strategies for this highly cherished species. Our results will inform other conservation efforts, including assisted migration of freshwater fish populations at the equatorial end of the geographical range limit of the species.     

Postpleistocene evolution of the brain?

The number of extraneurons (N_c) has been calculated with the formulae of Jerison ('63) for prehistoric population samples to check the hypothesis that N_c may not only increase by increasing of cranial capacity but also by decreasing of body-weight (gracilisation). Body weight of skeletal populations has been estimated by the formula of Debetz ('67). Samples from the Western part of Europe and Egypt support the hypothesis, but Eastern europoid samples display opposite relations: N_c increases with robusticity. It seems (as Jerison already suggested) that N_c is no measurement of the level of behavior in the populations of H. sapiens; but it may point towards allometric differences between West and East, which are also known for other characters.     

Genetic analysis of emerald ash borer (<Emphasis Type="Italic">Agrilus planipennis</Emphasis> Fairmaire) populations in Asia and North America

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is an invasive pest of North American ash (Fraxinus spp.) trees first discovered outside of its native range of northeastern Asia in 2002. EAB spread from its initial zone of discovery in the Detroit, Michigan and Windsor, Ontario metropolitan areas, in large part, from inadvertent human-assisted movement of infested ash materials. EAB infestations are now known in 15 US states and two Canadian provinces. The primary goal of this study was to use molecular markers to characterize the population genetic structure of EAB in its native and introduced range. This information may provide valuable insights on the geographic origin, potential host range, invasion potential, and additional biological control agents for ongoing management efforts of this destructive wood-boring beetle. EAB were collected from 17 localities in its native Asian range and from 7 localities in North America, and population structure analyzed using mtDNA gene sequences, AFLP fingerprints, and alleles at 2 microsatellite loci. Analysis of mtDNA cytochrome oxidase subunit I gene (COI; 439 bp) sequences revealed all North American individuals carry a common mtDNA haplotype also found in China and South Korea. Additional mtDNA haplotypes observed in China and South Korea differed from the common haplotype by 1–2 nucleotide substitutions and a single individual from Japan differed by 21 nucleotide changes (4.8%). Analysis using AFLP fingerprints (108 loci) indicated Asian populations were more highly variable, yet had less overall population structure, than the North American populations. North American populations appear most closely related to populations in our sample from the Chinese provinces of Hebei and Tianjin City. Further, population assignment tests assigned 88% of the individual beetles from North America to either Hebei or Tianjin City.