• The Plant Pathology Journal
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• v.25 no.4
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• pp.303-316
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• 2009

Genetic variation among the base isolates and monosporidial strains derived from these isolates of Tilletia indica- the causal agent of Karnal bunt (KB) in wheat, was analyzed by morphological, growth behaviors and RAPD-ISSR based molecular polymorphism. Genetic make up of fungal cultures vary among each other. The magnitude of variation in KBPN group is less (narrow genetic base) when compared to the other groups KB3, KB9 and JK (broad genetic base) reflecting that variability is a genetically governed process. The generation of new variation with different growth characteristics is not a generalized feature and is totally dependant on the original genetic make-up of the base isolate generating new monosporidial strains. Thus, it can be concluded that monosporidial strains derived from mono-teliosporic isolate, consists of genetically heterogeneous population. The morphological and genetic variability further suggests that the variation in T. indica strains is predominantly derived through the genetic rearrangements through para sexual means.

• The Korean Journal of Zoology
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• v.35 no.2
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• pp.219-225
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• 1992

The genetic variation in mitochondrial DNA (mtDNA) was analysed within and between two species of tree frogs. Hyla japonica and H. suweonensis from South Korea. Purified mtDNAs were digested with each of 11 restriction enLvmes which cleave at six base recognition sequences. The genome size of H. iaponica revealed ho types (20.0 $\pm$ 0.3 and 19.6 $\pm$ 0.3 kb) and this difference is explained by either addition or deletion of about 0.4 kb fragment. On the other hand, the genome sire of H. suueonensis was about 19.0 $\pm$ 0.4 kb only. For the analysis, level of fragment homology (F) and nucleotide sequence divergence (p) were estimated from comparisons of digestion profiles. Among four populations of H. iaponica, substantial mean sequence divergence was 0.017 (range 0.001-0.026); between identical types, 0.001 IslilaRl type) and 0.004 (Large type) respectively; between different ones, 0.024 (range 0.023-0.026). The level of sequence divergence between he species was 0.142 (range 0.131-0.146). This result suggested that he species ㅂwere distinctly differentiated species. The divergence time between ko species was estimated 7.1 million years.

• Animal cells and systems
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• v.4 no.3
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• pp.267-272
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• 2000

Partial sequence of the mitochondrial cytochrome b gene was analyzed to investigate genetic variation from 10 geographic populations of Granulilittorina exigua in Korea. The sequence of 282 base pairs was determined by PCR-directed silver sequencing method. The sequences of two species within the genus Littorina reserved in NIH blast search were utilized to determine geographic variations of species referred. The levels of mtDNA sequence differences were 0.00-2.54% within populations and 0.71-4.43% between populations. There were four amino acid differences between representative species of the genera Granulilittorina and Littorina, but no differences within populations of the genus Granulilittorina. The UPGMA and the N-J trees based on Tamura-Nei genetic distance matrix were constructed, which showed that the genus Granulilittorina was divided into three groups such as eastern (even exception for Tokdo population), southern, and western regional populations. The degrees of genetic divergence within populations of each group were p=0.021, p=0.019, and p=0.018, respectively. The divergence between the eastern and southern populations was p=0.032, showing closer relationship than with the western populations (p=0.052). Based on the diverged time estimation, the eastern and southern populations of Granulilittorina exigua in Korea diverged from the western populations about 2.1 MYBP, and the eastern and southern populations diverged from each other about 1.3 MYBP.

• Animal cells and systems
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• v.3 no.2
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• pp.199-205
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• 1999

The nucleotide sequences of a 504 bp segment of the mitochondrial cytochrome b gene were analyzed to survey the intraspecific variation of the brown frog, Rana dybowskii, collected from nine populations in South Korea. Comparisons of sequence divergence of the cytochrome b gene suggest that the populations examined are clearly classified into two types (type 1 and type 2), diverged from each other by a high value of 14.3-15.9% sequence divergence. The two types are distributed allopatrically in most populations, but only one population occurs sympatrically. In the Tonghae population, their spawning grounds differ in that type 1 spawns in the puddle and type 2 spawns in the mountain creek. Based on the genetic divergences of the cytochrome b gene sequences, the phylogenetic status of Korean R. dybowskii is elucidated by comparing it with related brown frogs distributed in an area adjacent to the Korean Peninsula. Interspecific sequence divergences among type 1, type 2 and other related brown frog species (Russian R. dybowskii, R. pirica, R. ornativentris, R. chensinensis: 2n=24 chromosomes) used in this study ranged from 11.7 to 16.3%. R. dybowskii in Tsushima is very similar to our type 1 (sequence divergence＝0-1.6%) and R. chensinensis in western China is closest to our type 2 (sequence divergence＝6.8-7.5%).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.306-313
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• 1994

In order to estimate the degree of genetic divergence between the two types of finespotted flounder, Pleuronichthys cornutus which is important commercially in Japan, isozyme analysis was carried out by starch gel electrophoresis. Twenty two loci coding for fourteen enzymes were scored in two types of finespotted flounder and three completely divergent loci (Acp, Idh-2 and Mdh-2), with no common alleles, were observed between these two types. Nei's genetic distance between two types was 0.46592. However, the expected average heterozygosity was 0.120 in type A (Hon meitagarei) and 0.095 in type B (Bake meitagarei) These results mean that the existence of two types of finespotted flounder was established in this study which may have had genetic divergence and the divergence time of these two types may have been about $2.3{\times}10^6$ years ago.

• Animal cells and systems
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• v.4 no.1
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• pp.31-37
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• 2000

The genetic variations among six species of Rana from Korea (R. nigro-maculata, R. piancyi, R. dybowskii, R. sp, R. rugosa type A, B and R. amurensis) were investigated using 499 bases of mitochondrial DNA sequences for ND2 (NADH dehydrogenase subunit 2) gene and $tRNA^{Trp}$ gene. Partial sequences of ND2 gene (427 bp) and full sequences of $tRNA^{Trp}$ gene (73 bp) were identified. The level of sequence divergences ranged from 0.2 to 5.2% within species and 4.9-28.0% among 6 species of the genus Rana. The $tRNA^{Trp}$ gene of the genus Rana was composed of 77 nucleotides which showed a two dimensional "cloverleaf" structure. The secondary structure of $tRNA^{Trp}$ was not found compensatory changes which could potentially confound phylogenetic inference. In the neighborjoining tree, brown frogs were clustered first with the level of sequence divergence of 13.20% between R. amurensis and R. dybowskii, and 9% between R. dybowskii and R. sp. supported by 99% bootstrap iterations, respectively. R. nigromaculata and R. plancyi were clustered into another group with 5.1% divergence supported by 100% bootstrap iteration. R. rugosa A 8nd B types were grouped by 4.9% divergence and clustered into the last group with other two groups with 100% bootstrap iterations.

• Journal of the Korean Institute of Intelligent Systems
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• v.10 no.5
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• pp.432-441
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• 2000

This paper deals with the fuzzy modeling for the complex and uncertain nonlinear systems, in which conventional and mathematical models may fail to give satisfactory results. Genetic algorithm has been used to identifY parameters and structure of fuzzy model because it has the ability to search optimal solution somewhat globally. The genetic algorithm, however, has a problem, which optimization process can be premature convergence in the case of lack of genetic divergence of population. Virus- evolutionary genetic algorithm(VEGA) could be a strategy against this local convergence. Therefore, we use VEGA for fuzzy modeling. In this method, local information is exchanged in population so that population can sustain genetic divergence. finally, to prove the theoretical hypothesis, we provide numerical examples to evaluate the feasibility and generality of fuzzy modeling using VEGA.

• The Journal of Korean Medicine
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• v.20 no.4
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• pp.62-68
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• 2000

This study was carried out to establish genetic understanding of three Sasang constitutions of Taeumin, Soeumin and Soyangin by Random Amplified Polymorphic DNA(RAPD) analysis. We have applied RAPD analysis to pooled DNA sample as a means to achieve rapid screening of large numbers of primers for their capacity to reveal constitutions-specific polymorphisms. From an initial 440 primers, 13 polymorphic primers between different constitutions were selected. Bandsharing(BS) and mean average percentage difference(MAPD) calculated within and between three constitutions using RAPD fingerprint data showed a higher degree of homogenity within than between the constitutions and indicated measurable divergence between three constitutions. The RAPD bandsharing(BS) values ranged from 0.71 to 0.73 between the three constitutions. The interconstitution divergence was narrower between Taeumin and Soeumin, than between the other paired constitution comparisons. The genetic distance between the three constitutions was measured by BS values. Genetic distance by RAPD analysis was 0.007 between Taeumin and Soeumin, and 0.014 between Soyang and the others. In conclusion, the genetic distance of Teaumin and Soumin was closer than that of Soyangin in the analysis of RAPD by using 440 primers.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.309-314
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• 2002

Random Amplified Polymorphic DNA (RAPD) assay was conducted to identify polymorphic markers in Amrithmahal, Krishna Valley, Hallikar, Deoni, Khillari, Ongole and Malnad Gidda breeds of South Indian cattle using twenty six primers. Of the 93 RAPD markers obtained, 53 were present in all breeds, 22 were individual specific and 18 were polymorphic for different breeds. Dual purpose breeds viz., Krishna Valley and Ongole showed less genetic divergence between them as compared to their genetic divergence from draft breeds viz., Amrithmahal, Hallikar and Khillari. Malnad Gidda was found to be a distinctly different from others studied.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.1
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• pp.23-32
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• 2007

The nature of genetic variation and diversity among the 65 multivoltine silkworm genotypes was evaluated for 16 post cocoon characters. The components of genetic variation revealed higher PCV (60.487%) and GCV (44.56%) for evenness (variation 1) followed by cohesion (PCV=55.38%, GCV=40.36%) and non-broken filament length (PCV=32.05%, GCV=31.28%). The higher heritability ($h^2$ in broad sense) was observed for boil-off loss (95.6%) followed by non-broken filament length (95.22%). The both genotypic and phenotypic correlation indicated significant positive correlation of filament length with non-broken filament length, silk recovery, raw silk, neatness, and low neatness; and negative correlation with denier, renditta and silk waste. The principal component analysis (PCA) revealed 75.381 % of total variance from the five principal components extracted. On the basis of Mahalonobis' $D^2$ values (Ward's minimum variance), the sixty-five multivoltine silkworm genotypes were classified in to 9 clusters with substantial inter and intra cluster distances. Number of genotypes included in different clusters varied from 3 to 17. The results indicated that the optimum distance obtained in cluster VII (15.059) along with higher cluster mean values especially for filament length, non broken filament length, renditta, silk recovery, silk waste, and raw silk emphasized the utilization of these genotypes in the conventional silkworm breeding programme for improvement of multivoltine silk fibre quality. The possibility of exploiting genetic variation in post cocoon traits for efficient breeding programme is discussed.