• Animal cells and systems
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• v.16 no.2
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• pp.145-153
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• 2012

The pear psylla, $Cacopsylla$ $pyricola$ (Hemiptera: Psyllidae), is a serious insect pest of commercial pear crops. The species, which resides on pear trees throughout its life cycle, is rapidly spreading in some regions of the world. The population genetic structure of the species collected from several pear orchards in Korea was studied to understand the nature of dispersal and field ecology of the species. The 658-bp region of mitochondrial COI gene and the 716-bp long complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA were sequenced. Unlike other previously studied insect pests, the COI-based genetic diversity of the pear psylla was extremely low (maximum sequence divergence of 0.15%). This finding allowed us to conclude that the species may have been introduced in Korea relatively recently. ITS2 sequence-based analyses of phylogeny, population differentiation, gene flow, and hierarchical population structure all concordantly suggested that the pear psylla populations in Korea are neither genetically isolated nor hampered for gene flow. These genetic data are concordant with the dispersal of an overwintering winterform morph outside the non-pear habitat in the fall.

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.243-248
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• 2009

After the original identification of canine parvovirus (CPV) type 2 (CPV-2) in 1978, new antigenic variants such as CPV-2a, CPV-2b and CPV-2c have become widespread in the most countries. In this study, the genetic analysis of canine parvovirus was investigated in a total of 13 CPV vaccines, which have been licensed in Korea since late 1980s, and a field isolate of CPV from a dog with CPV infection clinical symptom. The partial VP2 gene of CPV was amplified and sequenced from 13 vaccine strains and one field isolate. The results showed that of the 13 vaccine strains, 10 strains belong to the CPV-2, 2 strains to CPV-2b, the remaining and one isolate to CPV-2a type, respectively. Several mutations of amino acids were detected at residues of the critical region of the commercial vaccine strains. These data suggest that new type of vaccines containing CPV-2a or CPV-2b/2c type may be required for the better prevention of new CPV infection in dog population in Korea, because CPV-2 contained in most licensed vaccines has been replaced by antigenic variants designated CPV-2a or CPV-2b/c in the worldwide dog population.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1240-1244
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• 2006

The complete coding region sequence of the SRY gene in Chinese swamp buffalo was determined by PCR product sequencing. Comparison of swamp and river buffalo SRY gene sequences revealed a single nucleotide polymorphism (SNP, C/G) at the 202 bp site of the coding region. Further, a total of 124 male domestic buffaloes were genotyped at this SNP site using the PCR-SSCP method, and it was found that all Chinese indigenous swamp buffaloes had a guanine (G) at this site, while introduced river buffaloes and crossbred buffaloes showed a cytosine (C). Our findings suggested that this Y-linked SNP displayed type-specific alleles differentiating swamp and river buffaloes, and could be used as an effective marker to detect crossbreeding of swamp buffaloes with introduced river buffaloes in native buffalo populations, and thereby assess genetic diversity status and make proper conservation decisions for indigenous swamp buffaloes. In addition, this SNP can be potentially applied in the study of Asian water buffalo phylogeny from a male perspective.

• Journal of fish pathology
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• v.24 no.1
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• pp.1-9
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• 2011

Viral haemorrhagic septicaemia virus (VHSV) is an epidemic virus in olive flounder Paralichthys olivaceus farms in Korea, since the virus have first isolated in 2001. In the present study, partial glycoprotein (G) gene nucleotide sequences of seven Korean VHSV from cultured olive flounder and wild marine fishes in coastal areas of Korea were analyzed to evaluate their genetic relatedness to worldwide isolates. Phylogenetically, all Korean VHSV formed only one minor cluster including Japanese isolates, in genotype IVa, while the North America isolates formed a different minor cluster in genotype IVa. These results suggest that Korean VHSV could be an indigenous virus in Korean and Japanese coastal areas, but have not been introduced from North America.

• Animal Systematics, Evolution and Diversity
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• v.19 no.2
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• pp.217-225
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• 2003

This study was conducted to ascertain interspecific relationships by analyzing allozyme and soluble proteins of ten species in the Drosophila (Drosophila) to form a part of systematic studies of Korean drosophilids. The results of allozyme and TDE analysis showed that D. (D.) curvispina and D (D.) tsigana had the furthest genetic distance. On the other hand, the genetic distance between D (D.) angularis and D (D.) brachynephros was extremely close. And, ten species of the subgenus Drosophila can be divided into the first group of D. (D.) virilis, D. (D.) tsigana and D. (D.) lacertosa , and the second group consisted of four subgroups; the first subgroup clustered D. (D.) angularis and D (D.) brachynephros, the second subgroup clustered D. (D.) unispina and D. (D.) curvispina, the third subgroup of D (D.) takadai and D. (D.) kuntzei and the fourth subgroup of D. (D.) nigromaculata alone.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.62-63
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• 2005

Korean Ogol Chicken is a natural treasure in Korea and expected to be a valuable genetics resource in the world. As an initial step to investigate the genetic structures of this breed, phylogenetic analysis has been performed using mitochondrial DNA (mtDNA) sequence variations. Total 30 Korean Ogol Chickens were investigated in this study and they were grouped into 4 haplotypes, consisting 11 birds in the largest haplotype. Based on the phylogenetic analysis, chicken breeds were divided into three major groups and Korean Ogol Chicken were appeared all of these three groups indicating their large genetic mtDNA diversity. These results will be used for making breeding and conservation strategies for this breed.

• ALGAE
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• v.24 no.3
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• pp.129-138
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• 2009

DNA-based discrimination of species is a powerful way for morphologically otherwise similar species, like centric diatoms. Here, the author sequenced long-range nuclear ribosomal DNAs, spanning from the 18S to the D5 region of the 28S rDNA, of Stephanodiscus, particularly including a Korean isolate. By comparisons, high DNA similarities were detected from the rDNAs of nine Stephanodiscus (>99.4% in 18S rDNA, >98.0% in 28S rDNA). Their genetic distances, however, were significantly different (Kruskal-Wallis test, p < 0.01) compared to two related genera, namely Cyclotella and Discostella. In addition, genetic distances of 18S rDNAs were significantly different (Student’s t-test, p = 0.000) against those of the 28S rDNAs according to individual genera (Cyclotella, Discostella, and Stephanodiscus). Phylogenetic analyses showed that Stephanodiscus and Discostella showed a sister taxon relationship, and their clade was separated from a cluster of Cyclotella (1.00 PP, 100% BP). This suggests that Stephanodiscus has highly conserved sequences of both 18S and 28S rDNA; however, Stephanodiscus is well-separated from other freshwater centric diatoms, such as Cyclotella and Discostella, at the generic level.

• Animal Systematics, Evolution and Diversity
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• v.15 no.1
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• pp.11-25
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• 1999

Two problematic subgenera of Tomoceridae (Collembola, Insecta) were investigated for their phylogenetic relationships based on morphological characters and allozyme study from three relevant species. Different dendrograms were obtained obtained between morphological and allozyme studies. The morphological data did not give rise to any result distinctive enough to separate the two subgenera whereas the allozyme analysis produced a clear separation by the high genetic distance value. They were consistent, however, whether given rise to by using distance or cladistic methods and also whether character weighting or unweighting approaches employed in the morphological character analysis. As a consequence, it is strongly suggested that any prominent morphological trait might work as a good taxonomical character when supported by a strong genetic divergence as evidenced by allozyme analysis for instance.

• Journal of Apiculture
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• v.33 no.4
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• pp.227-237
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• 2018

The majority parasitic bee mites of Thailand in genus Tropilaelaps are infesting colonies of native bees (Apis dorsata) and introduced bees (A. mellifera). The investigation aims to study morphological and genetic variation of Tropilaelaps mites infected different hosts. Adult mites were collected from honey bee brood throughout Thailand. Traditional and geometrical morphometrics were measured on photograph by using TPS program. Additional, COI gene variations were examined by PCR-RFLP and nucleotides sequencing. Tree of mites relationships were constructed by NJ and MP assumptions. Morphometric results indicated T. mercedesae were major species infesting on A. dorsata and A. mellifera. Mophological variation represented at anal and epigynial plate, which the shape of the anal plate apex margin has been key character to identify between T. mercedesae (bell to blunt shape) and T. koenigerum (pear shape). However, the discriminant analysis suggested that geometric results were potential to classify Thai Tropilaelaps populations from different hosts better than traditional morphometric. Otherwise, PCR-RFLP clearly detected the site of Dra I and Xba I digestion of Thai Tropilaelaps morphotypes. The COI sequences of T. koenigerum were founded infesting only A. dorsata in Thailand and four sequences that related to the Thai T. mercedesae morphotypes. The NJ and MP tree were clearly classified Thai Tropilaelaps species which were suggested both from morphological and molecular analysis. This information might be basically of taxonomic status, but this should have implication for controlling these mites in Thailand and other countries.

• Animal Systematics, Evolution and Diversity
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• v.30 no.2
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• pp.87-94
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• 2014

Specimens of the genus Orobdella Oka, 1895 from Korea, including various locations in the Korean Peninsula, were identified as Orobdella tsushimensis Nakano, 2011. Phylogenetic analyses using mitochondrial cytochrome oxidase subunit 1 (COI), ND1, $tRNA^{Cys}$, $tRNA^{Met}$, 12S rRNA, $tRNA^{val}$, and 16S rRNA markers show that the newly collected specimens form a monophyletic group with the known O. tsushimensis specimens. The genetic distance of COI of these specimens was in the range 0.4-6.6%. These results confirm that the newly collected specimens belong to O. tsushimensis. This is the first record of the genus Orobdella from the Korean Peninsula.