• Animal Systematics, Evolution and Diversity
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• v.25 no.3
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• pp.325-329
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• 2009

Lepomis macrochirus from the family Centrarchidae, commonly known as Bluegill sunfish, is an introduced freshwater fish in Korea that thrives in lakes, ponds, reservoirs and rivers. Since its introduction into Korea in 1969, Lepomis macrochirus has rapidly dispersed out and increased in number almost all over the freshwater ecosystems in Korea. Consequently this species causes a severe ecological problem, threatening native fishes due to its omnivorous foraging behaviors upon fish juveniles and many freshwater invertebrates. To address population genetic structure of L. macrochirus, 74 fish samples from 10 populations were collected and compared for their mitochondrial D-loop control region. As the result we found that the genetic diversity of L. macrochirus is extremely low such as resulting only four haplotypes with a few nucleotide differences among them. Analysis of molecular variance (AMOVA) revealed that the source of population genetic variation is largely retained in the comparisons among individuals within populations, while it is relatively low with slight significance at the highest hierarchical group. This distribution pattern differs from what is expected when biogeography is under the influence of natural geographic barriers such as mountain ranges in Korea. Instead the result is accord with the influential role of random spreading events facilitated by local people for aquaculture and fishing, and subsequent dispersals since its single point of introduction into Korea.

• Animal cells and systems
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• v.13 no.3
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• pp.305-314
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• 2009

The control region of mitochondrial DNA (13516-14619) is located between srRNA and $tRNA^{lle}$ gene in swimming crab, Portunus trituberculatus. The present study was investigated the genetic polymorph isms of the control region in samples of P. trituberculatus collected at coastal waters of the Yellow Sea in Korea. A total of 300 substitution and indel polymorphic sites were identified. In addition to SNPs and indel variation, a hypervariable microsatellite motif was also identified at position from 14358 to 14391, which exhibited 10 alleles including 53 different suballeles. When the hypervariable microsatellite motif was removed from the alignment, 95 haplotypes were identified (93 unique haplotypes). The nucleotide and haplotype diversities were ranged from 0.024 to 0.028 and from 0.952 to 1.000, respectively. The statistically significant evidence for geographical structure was not detected from the analyses of neighbor-joining tree and minimum-spanning network, neither. This result suggest that population of P. trituberculatus are capable of extensive gene flow among populations. We believed that the polymorph isms of the control region will be used for informative markers to study phylogenetic relationships of P. trituberculatus.

• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.221-234
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• 2003

Phylogenetic studies would clarify the diversity of fishes if the morphological analysis based on plesimorphy characters combined with new genetic analysis on molecular level, inferring more accurate and objective phylogeny and the taxonomy. Current molecular phylogenetic approach using mitochondrial genome provides the framework for a new hypothesis not only inferring the relationships between ancestor descendants but raveling the intra-, interspecies variation.

• Animal cells and systems
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• v.8 no.3
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• pp.231-233
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• 2004

Sequences of cytochrome b gene and control region of mitochondrial DNA from Korean common otters (Lutra lutra lutra L.) were examined to provide the genetic information for the conservation of this subspecies. Two haplotypes and one haplotype were revealed in cytochrome b gene and control region, respectively. The available sequences of European common otter (L. l. lutra) from GenBank were compared together with those of Korean common otter in order to determine the degree of sequence variation between them. In cytochrome b gene sequences, two haplotypes from Korea and two haplotypes of Europe showed differences in 12 of 1,045 sites. The Tamura-Nei nucleotide distances between two European haplotypes was 0.10% and those between two Korean haplotypes was also 0.10%, but those between Korean haplotypes and European ones ranged from 0.96% to 1.16%. In the control region, one Korean haplotype and seven European ones showed differences in seven of 300 sites; the Tamura-Nei distances among seven European haplotypes were 0.34% to 1.01%, but those between Korean haplotype and European ones ranged from 1.01% to 1.69%. Although further molecular and morphological studies with specimens from eastern Asia including Amur region and northeast China are needed, it is possible that the Korean common otter might be closer or identical to the far-eastern Asian common otter, L. l. amurensis Dybowski.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.107-112
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• 2007

The mole crickets, Gryllotalpa, are insect pest distributed in the world. In Korea, G. orientalis was reported to occur, but previous ecological studies suggested the presence of two ecological types. To test this hypothesis, we sequenced a portion of mitochondrial (mt) genome from 48 G. orientali individuals collected over five Korean localities: Busan, Suwon, Okchon, Wonju, and Gangneung. From the sequence analysis, only two haplotypes were obtained, but the sequence divergence between the two haplotypes was 11 %, suggesting the presence of two distinct genetic groups in Korea. Although the population of Busan, Okchon, Wonju, and Gangneung was identified as a single haplotype, but that of Suwon was occupied by both hapotypes. Considering sequence divergence of other insect species occurring in Korea, the divergence estimate found between the two haplotypes seems to be too large to be considered as identical species. This result may suggest that the two differentiated haplotypes found in this study may reflect the previously reported two ecological types found in Suwon, Korea. To further understand the genetic divergence of the two phylogenetic groups, analysis of more variable regions of G. orientalis genome is required.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.1
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• pp.9-17
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• 2000

Genetic variation in the domestic silkworm strains (Bombyx mori) and phylogenetic relationships between domestic silkworms and wild silkworms (B. mandarina) were investigated by using a portion of mitochondrial CGI gene sequences. Ten geographic strains of B. mori we sequenced were identical in the 410 bp-section of mitochondrial COI gene. This sequence was also identical to the homologous sequence of the four Gen-Bank-registered strains, but one strain of B. mori differed a single nucleotide (0.2%) from others. MtDNA homogeneity in the B. mori strains appears to be resulted from fixation into the mast frequent mtDNA type during the course of breeding for new strains, in which an extensive indoor rearing and removal of unwanted individuals were accompanied. In the comparisons between domestic and wild silkworms, some wild silkworms were closely related to domestic silkworms (0.2%-1.2% of divergence), but the others were not (2.7%-3.7% of sequence divergence). This result was also reflected in the phylogenetic analyses, showing two independent phylogenetic groups: one including all B. mandarina sequences and the other including both B. mandarina and B. mori sequences. Thus, domestic silkworms may have been derived from the ancestor of B. mandarina, which belongs to this group, alto-ough more extensive study will provide better understanding on this issue.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.181-191
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• 2000

We have sequenced a portion of mitochondrial CO! gene (403 bp) of the firefly, Pyrocoelia rufa, to investigate genetic diversity within population, geographic variation, and phylogenetic relationships among haplotypes. A total of seven mtDNA haplotypes ranging in sequence divergence from 0.2% to 1.2% were obtained from 26 fireflies collected at four localities in Korea: Namhae, Pusan, Muju, and Yongin. The samples collected at the urban area, Pusan, were all fixed with one haplotype, differently those collected at the forest and/or agricultural areas. This appears to suggest that habitat fragmentation and population bottleneck caused by urbanization might have been severe in Pusan. On the other hand, from Muju known as the largest habitat and sanctuary for the firefly, four haplotypes with the maximum sequence divergence of 1.0% were obtained, and this estimate was the highest among the areas studied. The fireflies collected at the isolated islet, Namhae, revealed relatively low haplotype diversity(H=0.25), but one haplotype (PR7) was phylogenetically differentiated from others. This phenomenon was explained in terms of biogeographic history of the island and gene flow in the recent past. Grouping of Muju- Y ongin and Pusan-Namhae, respectively, in the hierarchical genetic analysis suggests the presence of historically occurred, biogeographic barrier against gene flow between them.

• Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.145-158
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• 2024

Life history characteristics, habitat landscape, and historical events are believed to have shaped the patterns of genetic variation in many taxa. The bony lip barb, Osteohilus vittatus, represent a potamodromous fish that complete all life cycle in freshwater and is widely distributed in Southeast Asia. It usually lives in small rivers and other freshwater habitats, and movement between habitats for either food or reproduction has been typical. These life history characteristics may promote gene flow, leading to less structured populations. However, many freshwater habitats are fragmented, which restricts gene flow. We investigate how this interplay has shaped patterns of genetic variation and phylogeographic structure within this species in the Sundaland, a biodiversity hotspot with a complex geological history, using mitochondrial cytochrome oxidase I (mtCOI) as a genetic marker. Forty-six mtCOI sequences of 506 bp long were collected from ten localities, eight geographically isolated and two connected. The sequences were used for population genetic and phylogeographic analyses. Our results showed a low genetic diversity within populations but high between populations. There was a deep phylogeographic structure among geographically isolated populations but a lack of such structure in the connected habitats. Among geographically isolated populations, sequence divergence was revealed, ranging from 1.8% between Java and Sumatra populations to 12.2% between Malaysia and Vietnam. An indication of structuring was also observed among localities that are geographically closer but without connectivity. We conclude that despite high dispersal capacity, the joint effects of historical events, long-term geographic isolation associated with sea level oscillation during the Pleistocene, and restricted gene flow related to lack of habitat connectivity have shaped the phylogeographic structure within the O. vittatus over the Sundaland.

• Parasites, Hosts and Diseases
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• v.58 no.1
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• pp.93-97
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• 2020

The cestode Taenia hydatigena uses canids, primarily dogs, as definitive hosts, while the metacestode larval stage cysticercus infects a range of intermediate hosts, including domestic animals such as goats, sheep, and pigs. Cysticercosis due to T. hydatigena has large veterinary and economic drawbacks. Like other taeniids, e.g., Echinococcus, intraspecific variation is found among the members of the genus Taenia. In Africa, few studies are available on the epidemiology and distribution of T. hydatigena, and even fewer studies are available on its genetic variation. In this study, we molecularly identified 11 cysticerci from sheep in Sudan and demonstrated the genetic variation based on the NADH dehydrogenase subunit 1 (nad1) and cytochrome c oxidase subunit 1 (cox1) mitochondrial genes. The isolates were correctly identified as T. hydatigena with more than 99% similarity to those in the GenBank database. Low diversity indices and insignificant neutrality indices were observed, with 3 and 2 haplotypes for the nad1 and cox1 genes, respectively. The results suggest the presence of unique T. hydatigena haplotypes in Sudan, as haplotypes with 100% similarity were not found in the GenBank database. With few available studies on the genetic variation of T. hydatigena in Africa, this report represents the first insights into the genetic variation of T. hydatigena in Sudan and constitutes useful data.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.12
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• pp.1905-1911
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• 2020

Objective: Tibetan pigs, an excellent species unique to China, face serious threats, which in turn affects the development and utilization of the outstanding advantages of plateau hypoxia adaptability and reduces their genetic diversity. Therefore, a discussion of measures to conserve this genetic resource is necessary. The method, based on genetic diversity, genetic divergence and total genetic contribution rate of population, reflects the priority conservation order and varies depending on the three different purposes of conservation. Methods: We analyzed mitochondrial DNA control region (D-loop) variation in 1,201 individuals from nine Tibetan pig populations across five provinces and downloaded 564 mtDNA D-loop sequences from three indigenous pig breeds in Qinghai, Sichuan, and Yunnan Provinces distributed near the Tibetan pigs. Results: We analyzed three different aspects: Changdu Tibetan pigs have the highest genetic diversity, and from the perspective of genetic diversity, the priority conservation is Changdu Tibetan pigs. Hezuo Tibetan pigs have the highest genetic contribution, so the priority conservation is Hezuo Tibetan pigs in the genetic contribution aspect. Rkaze Tibetan pigs were severely affected by indigenous pig breeds, so if considering from the perspective of introgression, the priority conservation is Rkaze Tibetan pigs. Conclusion: This study evaluated genetic diversity and comprehensively assessed conservation priority from three different aspects in nine Tibetan pig populations.