• Animal Systematics, Evolution and Diversity
• /
• v.28 no.4
• /
• pp.269-278
• /
• 2012

Gobiids are hyperdiverse compared with other teleost groups, with about 2,000 species occurring in marine, freshwater, and blackish habitats, and they show a remarkable variety of morphologies and ecology. Testing the effectiveness of DNA barcodes on species that have emerged as a result of radiation remains a major challenge in evolutionary biology. Here, we used the cytochrome c oxidase subunit 1 (COI) sequences from 144 species of gobies and related species to evaluate the performance of distance-based DNA barcoding and to conduct a phylogenetic analysis. The average intra-genus genetic distance was considerably higher than that obtained in previous studies. Additionally, the interspecific divergence at higher taxonomic levels was not significantly different from that at the intragenus level, suggesting that congeneric gobies possess substantial interspecific sequence divergence in their COI gene. However, levels of intragenus divergence varied greatly among genera, and we do not provide sufficient evidence for using COI for cryptic species delimitation. Significantly more nucleotide changes were observed at the third codon position than that at the first and the second codons, revealing that extensive variation in COI reflects synonymous changes and little protein level variation. Despite clear signatures in several genera, the COI sequences did resolve genealogical relationships in the phylogenetic analysis well. Our results support the validity of COI barcoding for gobiid species identification, but the utilization of more gene regions will assist to offer a more robust gobiid species phylogeny.

• Journal of Life Science
• /
• v.26 no.7
• /
• pp.749-757
• /
• 2016

This study was carried out to reveal the genetic population structure of the Jeju Island population and the phylogenetic relationship of East Asian populations of the large-footed bat (Myotis macrodactylus) based on the genetic polymorphisms of mitochondrial cytochrome B (CYTB) and NADH dehydrogenase subunit 1 (ND1) gene sequences. A total of fourteen and nine haplotypes were found in the CYTB and ND1 sequences from East Asian bats, respectively. Haplotype distribution showed locality specific patterns. The results from ND1 haplotype analysis showed that the Jeju Island population has four haplotypes: the Mt. Halla and Western subpopulations have three ND1 haplotypes, but the Eastern subpopulation has just a single haplotype Nd03, which is commonly found on this island. The neighbor-joining (NJ) tree showed the closer relationship between Jeju Island and Japan rather than that between Jeju and Gangwon-do Province. The divergence time between the maternal ancestor lineages of Japanese and Chinese populations was estimated to be 0.789±0.063 MYBP. The secondary divergence between Jeju and Japanese bats was calculated about to be 0.168±0.013 MYBP. The Jeju population has immigrated to the island at least fifty thousand years ago. In addition, ND1 haplotype analysis suggested that the insular bats have experienced at least two further genetic differentiation events within this island. Consequently, these findings suggested that the results of this study may play a critical role in understanding the phylogenetic relationship among East Asian bat populations of M. macrodactylus. To prepare more explainable information on evolutionary correlation, analysis is still required to examine using expanded samples from China, Russia, and southern parts of the Korean Peninsula.

• Journal of Plant Biology
• /
• v.38 no.1
• /
• pp.39-45
• /
• 1995

Glycine soja Sieb. et Zucc., a predominantly selfing annual, has been served as a reservoir of germplasm for soybean, G. max (L.) Merr., cultivar improvement. This study describes the levels and distribution of genetic variation within and among 22 Korean populations of G. soja using starch gel electrophoresis. The species maintains very similar levels of genetic variability within populations observed in most other annuals. At the population level, the mean percent of polymorphic loci (P) was 32.6%, mean number of allele per locus (A) was 1.32, and mean expected heterozygosity (He) was 0.112. In addition, total genetic diversity (HT) calculated only for polymorphic loci was 0.347. However, significant differences in allele frequencies among populations were found for all loci (P<0.001 in each case) and, on average, about 70% of the total variation in the species is common to all populations. Indirects estimate of the number of migrants per generation (Nm=0.58, calculated from mean GST) indicates that gene flow is low among Korean populations of the species. In addition, analysis of fixation indices revealed a substantial heterozygote deficiency in most populations and at all loci. This indicates that most populations sampled may have been substructed largely due to inbreeding (predominantly selfing) and restricted gene flow, coupled with founder effect and genetic drift. Considering a high genetic divergence among populations, it is recommended that several Korean populations of the species should be preserved, especially such as populations in the eastern and southeastern Korean peninsula with high variation.

• Journal of Korean Society of Forest Science
• /
• v.98 no.5
• /
• pp.531-538
• /
• 2009

We used enzyme electrophoresis to evaluate genetic diversity in five populations of endemic ash, Fraxinus chiisanensis in Korea. Of 15 putative allozyme loci examined 26.7% were polymorphic and expected heterozygosity for the species was low (0.082). Within the range, population were highly differentiated ($F_{ST}$=0.356) and little genetic variation was explained by geography. The pattern of distribution of variation showed low genetic variation within populations and pronounced divergence among populations, which was consistent with the prediction for the effects of limited gene flow and local genetic erosion. Although the frequencies of male plants were dominant ranging from 79.3% to 89.4%, most mating events seems to be inevitable mating between relatives in small populations based on heterozygote deficiency of this species. Small effective population size and the limited dispersal contributed to the low rates of gene flow within as well as between populations.

• Animal cells and systems
• /
• v.4 no.1
• /
• pp.39-44
• /
• 2000

To assess the genetic diversity and population structure of Korean K. borealis, allozyme analysis was performed. The average genetic variability of Korean K. borealis populations was %P=13.2, Ho=0.048, and He=0.045. This value was the lowest in comparison with other Korean amphibian species studied. Also, the value was much lower than that of a reference population from Chinese K. borealis (%P=50, Ho=0.125, He=0.172). Wright's F-statistics showed that Korean K. borealis has distinctly low level of gene flow among regional populations (F$_{ST}$=0.339, Nm=0.487) in comparison with other Korean amphibian species studied. However, the average level of genetic divergence among Korean K. borealis populations was moderate (Nei's D=0.020). Therefore, it appeared that low levels of genetic diversity (He=0.045) and gene flow (Nm=0.487) among regional populations ave probably due to the results of decreasing population size and patchy distribution of this species in Korea.

• Korean journal of applied entomology
• /
• v.56 no.2
• /
• pp.107-120
• /
• 2017

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 550 COI gene sequences of B. tabaci. Genetic divergence within B. tabaci ranged from 0% to 27.8% (average 11.1%). This result indicates that the B. tabaci complex is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 217 COI gene sequences without duplications revealed that the B. tabaci complex is composed of a total of 43 putative species, including a new species, Java. In addition, genetic divergence within nine species (Australia, Asia II 1, Asia II 6, Asia II 7, Asia II 10, Mediterranean, New world, New world 2, Sub Saharan Africa 1) indicates that 4.0% is reasonable to be used as a threshold of species boundaries within the B. tabaci complex, and species with high intraspecific genetic divergences can be related with cryptic species.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.27 no.1
• /
• pp.142-158
• /
• 2013

The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is widely utilized for greenhouse pollination in South Korea. Understanding the magnitude of genetic diversity and geographic relationships is of fundamental importance for long term preservation and utilization. As a first step, we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to the "DNA barcode" region and the complete internal transcribed spacer 2 (ITS2) of nuclear ribosomal DNA from 88 individuals collected in nine South Korean localities. The complete ITS2 sequences were longest among known insects, ranging in size from 2,034 bp ~ 2,052 bp, harboring two duplicated 112-bp long repeats. The 658-bp long mtDNA sequences provided only six haplotypes with a maximum sequence divergence of 0.61% (4 bp), whereas the ITS sequences provided 84 sequence types with a maximum sequence divergence of 1.02% (21 sites). The combination of the current COI data with those of published data suggest that the B. ignitus in South Korea and China are genetically a large group, but those in Japan can be roughly separated into another group. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population were found to exist among the South Korean populations of B. ignitus, which suggests panmixia. This finding is consistent with our understanding of the dispersal capability of the species.

• ALGAE
• /
• v.30 no.3
• /
• pp.183-195
• /
• 2015

The dinoflagellate genus Pelagodinium is genetically classified in distinct sub-clades and subgroups. However, it is difficult to determine whether this genetic diversity represents intra- or interspecific divergence within the genus since only the morphology of the type strain of the genus Pelagodinium, Pelagodinium bei, is available. An isolate associated with the genus Pelagodinium from Shiwha Bay, Korea, was recently cultured. This isolate was clustered with 3 to 4 strains from the Atlantic Ocean, Mediterranean Sea, and Indian Ocean. This cluster was distinct from the subgroup more closely associated with P. bei. The morphology of the isolate was analyzed using optical and scanning electron microscopy and was almost identical to that of P. bei except that this isolate had two series of amphiesmal vesicles (AVs) in the cingulum, unlike P. bei that has one series. When the pigment compositions of the isolate and P. bei were analyzed using high-performance liquid chromatography, these two strains had peridinin as a major accessory pigment and their pigment compositions were almost identical. In addition, the swimming behaviors of these two strains were very similar. The reexamination of the type culture of P. bei revealed two series in the cingulum as for the isolate. The new findings on the number of series of AVs in the cingulum, the pigment composition, and the swimming behaviors suggest that P. bei and the isolate are conspecific despite their genetic divergence. This study provides a basis to further understand the molecular classification within Pelagodinium combining genetic, morphological, pigment, and behavioral data.

• Journal of Life Science
• /
• v.8 no.4
• /
• pp.360-365
• /
• 1998

The genetic of a recently described virus, hepatitis G virus(HGV) was investigated. HGV envelope 1 (E1) nucleotide sequences isolated from six Korean hepatitis b virus-positive patients by using a reverse transcription-poly-merase chain reaction procedure, were analysed and compared to the seven previously reported HGV isolates. Sequence homology among the Korean isolates was 88-97% whereas among the isolates from different geographic areas was 80-92%, indicating geographical divergence of HGV. Nucleotide substitutions spread uniformly throughiut the E1 fragment. Furthermore, compared to the prototype HGV sequence, frameshift mutations were observed in most of the Korean isolating that a different translating initiation site for the polyprotein exists in the Korean type HGV.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.26 no.2
• /
• pp.95-112
• /
• 2013

As a first step toward understanding the divergence and relationships of the Nymphalidae (Lepidoptera: Papilionoidea) occurring in South Korea, cytochrome oxidase subunit I (COI), 16S ribosomal RNA (16S rRNA), and elongation factor-$1{\alpha}$ (EF-$1{\alpha}$) that comprise 3,501-3,716 bp were either sequenced (55 species) or the sequences were obtained from GenBank (23 species). The concatenated sequence divergence of six nymphalid subfamilies ranked in the following order: Danainae (10.3%), Satyrinae (9.5%), Limenitidinae (8.0%), Apaturinae (7.0%), Nymphalinae (6.7%), and Heliconiinae (6.2%). As has been reported in previous large scale international studies, the subfamilial relationships of (((((Limenitidinae + Heliconiinae) + (Nymphalinae + Apaturinae)) + Satyrinae) + Libytheinae) + Danainae) were also confirmed, except for the switched positions between Danainae and Libytheinae, and supported all subfamilies and tribe monophylies. Unlikely consistent phylogenetic relationships among genera within the majority of tribes in Nymphalidae, a conflicting relationship within the subfamily Apaturinae was obvious, presenting Apatura as sister to either Mimathyma or (Mimathyma + (Sephisa + (Hestina + Sasakia))), and both of these relationships are unconventional. Within the subfamily Limenitidinae, the genus Neptis was consistently revealed as a paraphyletic with respect to the genus Aldania, requiring further taxonomic investigation of the genus. Although limited, current sequence information and phylogenetic relationships are expected to be helpful for further studies.