• Title/Summary/Keyword: Population

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Genetic Variation and Differences within and between Populations of Cultured and Wild Bullhead (Pseudobagrus fulvidraco) Revealed by RAPD-PCR

  • Yoon Jong-Man;Kim Gye-Woong;Park Hong-Yang
    • Reproductive and Developmental Biology
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    • v.29 no.4
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    • pp.213-221
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    • 2005
  • We used nine decamer primers to generate DNA fragment sizes ranging from 100 bp to 1,600 bp from two bullhead (Pseudobagrus fulvidraco) populations of Dangjin in Korea. 376 fragments were identified in the cultured bullhead population, and 454 in the population of wild bullhead from Dangjin: 287 specific fragments $(76.3\%)$ in the cultured bullhead population and 207 $(45.6\%)$ in the wild bullhead population. On average, a decamer primer was used to generate 34.2 amplified products in a cultured bullhead. A RAPD primer was used to generate an average of 3.1 amplified bands per sample, ranging between 2.5 and 6.0 fragments in this population. Nine primers also generated 24 polymorphic fragments (24/376 fragment, $6.4\%$) in the cultured bullhead population, and 24 (24/454 fragments, $5.2\%$) in the wild bullhead population. The OPA-16 primer, notably, produced which 11 out of 11 bands $(100\%)$ were monomorphic in the wild bullhead population. 110 intra-population-specific fragments, with an average of 12.2 per primer, were observed in the cultured bullhead population. 99 fragments, with an average of 11.0 per primer, were identified in the wild bullhead. Especially, 55 inter-population-common fragments, with an average of 6.1 per primer, were observed in the two bullhead populations. The bandsharing value (BS value) of individuals within the wild bullhead population was substantially higher than was determined in the cultured bullhead population. The average bandsharing value was $0.596\pm0.010$ within the cultured bullhead population,. and $0.657\pm0.010$ within the wild bullhead population. The dendrogram obtained with the nine primers indicates two genetic clusters, designated cluster $1\;(CULTURED\;01\~CULTURED\;11)$, and cluster $2\;(WILD\;12\~WILD\;22)$. Ultimately, the longest genetic distance displaying significant molecular differences was determined to exist between individuals in the two bullhead populations, namely between individuals WILD no. 19 of the wild bullhead population and CULTURED no. 03 of the cultured bullhead population (genetic distance = 0.714). RAPD-PCR allowed us to detect the existence of population discrimination and genetic variation in Korean population of bullhead. This finding indicates that this method constitutes a suitable tool for DNA comparison, both within and between individuals, populations, species, and genera.

Census Population vs. Registration Population: Which Population Denominator Should be used to Calculate Geographical Mortality (센서스인구 대 주민등록인구: 지역별 사망률 연구에서 어느 인구를 분모로 사용하여야 하나?)

  • Hwang, In-A;Yun, Sung-Cheol;Lee, Moo-Song;Lee, Sang-Il;Jo, Min-Woo;Lee, Min-Jung;Khang, Young-Ho
    • Journal of Preventive Medicine and Public Health
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    • v.38 no.2
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    • pp.147-153
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    • 2005
  • Objectives: Studies on the geographical differences in mortality tend to use a census population, rather than a registration population, as the denominator of mortality rates in South Korea. However, an administratively determined registration population would be the logical denominator, as the geographical areas for death certificates (numerator) have been determined by the administratively registered residence of the deceased, rather than the actual residence at the time of death. The purpose of this study was to examine the differences in the total number of a district population, and the associated district-specific mortality indicators, when two different measures as a population denominator (census and registration) were used. Methods: Population denominators were obtained from census and registration population data, and the numbers of deaths (numerators) were calculated from raw death certificate data. Sex- and 5-year age-specific numbers for the populations and deaths were used to compute sex- and age-standardized mortality rates (by direct standardization methods) and standardized mortality ratios (by indirect standardization methods). Bland-Altman tests were used to compare district populations and district-specific mortality indicators according to the two different population denominators. Results : In 1995, 9 of 232 (3.9%) districts were not included in the 95% confidence interval (CI) of the population differences. A total of 8 (3.4%) among 234 districts had large differences between their census and registration populations in 2000, which exceeded the 95% CI of the population differences. Most districts (13 of 17) exceeding the 95% CI were rural. The results of the sex- and age-standardized mortality rates showed 15 (6.5%) and 16 (6.8%) districts in 1995 and 2000, respectively, were not included in the 95% CI of the differences in their rates. In addition, the differences in the standardized mortality ratios using the two different population denominators were significantly greater among 14 districts in 1995 and 11 districts in 2002 than the 95% CI. Geographical variations in the mortality indicators, using a registration population, were greater than when using a census population. Conclusion: The use of census population denominators may provide biased geographical mortality indicators. The geographical mortality rates when using registration population denominators are logical, but do not necessarily represent the exact mortality rate of a certain district. The removal of districts with large differences between their census and registration populations or associated mortality indicators should be considered to monitor geographical mortality rates in South Korea.

Geographical Variations and Genetic Distances of Three Saxidomus purpuratus Populations ascertained by PCR Analysis

  • Yoon, Jong-Man
    • Development and Reproduction
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    • v.19 no.4
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    • pp.259-264
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    • 2015
  • Genomic DNA samples isolated from geographical purplish Washington clam (Saxidomus purpuratus) were obtained from three different regions in the Korean Peninsula: Geoje (Geoje population; GJP), Gunsan (Gunsan population; GSP) and a site of North Korea (North Korea population; NKP). The seven primers generated the total 369 loci that can be scored from the GSP clam population. 356 fragments were generated from the NKP clam population. The complexity of the banding patterns varies dramatically between the primers and three localities. In this study, 319 loci were identified in the purplish Washington clam from Geoje and 369 in the clam population from Gunsan: 221 specific loci (69.3%) in the GJP clam population and 300 (81.3%) in the GSP population. These results demonstrate that the primer detected a large quantity of specific fragments, suggesting that the genetic variation in the GSP is higher than in the GJP population. In particular, the BION-28 primer gave DNA profiles with more fragments than the other six primers in the NKP population. The oligonucleotides primer BION-75 produced 21 unique loci to each population, which were ascertaining each population, approximately 250 bp, 300 bp and 400 bp, in the GJP population. Outstandingly, the primer BION-50 detected 21 shared loci by the three populations, major and/or minor fragments of sizes 150 bp, which were matching in all samples. With regard to average bandsharing value (BS) results, individuals from GJP population (0.743) displayed higher bandsharing values than did individuals from GSP population (0.606). In the present study, the dendrogram gained by the seven oligonucleotides primers indicates three genetic clusters: cluster 1 (GEOJE 01 ~ GEOJE 07), cluster 2 (GUNSAN 08 ~ GUNSAN 14), cluster 3 (N.KOREA 15 ~ N.KOREA 21). Among the twenty one clams, the shortest genetic distance that revealed significant molecular differences was between individuals 08 and 09 from the NKP population (genetic distance = 0.073), while the longest genetic distance among the twenty-one individuals that demonstrated significant molecular differences was between individuals GEOJE no. 03 and GUNSAN no. 09 (genetic distance = 0.669). Comparatively, individuals of GJP population were properly closely related to that of NKP population, as revealed in the hierarchical dendrogram of genetic distances. In due course, PCR analysis has revealed the significant genetic distance among three purplish Washington clam populations. PCR fragments discovered in this study could be valuable as a DNA marker of the three geographical clam populations to distinguish.

A Study on the Application of Building Population Weighting to ERAM Model Based on GIS Data (GIS 데이터에 기반한 건물인구 가중치 적용 ERAM 모델에 관한 연구)

  • Mun, Sunghoon;Piao, Gensong;Choi, Jaepil
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.1
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    • pp.47-54
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    • 2019
  • This study proposes a new ERAM model with building population weighting. Previous studies of applying weightings on ERAM model on the scale of urban space were focused on the relationship between the street and the human behavior. However, this study focuses on the influences that buildings give to human behavior and develops a building population weighted ERAM model. This research starts by analyzing ERAM model to its basic compositions, which are adjacency matrix and row vector. It applies building population weighting to the row vector, while previous studies put weightings in the adjacency matrix. Building population weighted ERAM model calculates the building population weighting based on GIS data, which provides objective and massive data of buildings in the urban scale. For the verification of the model, Insa-dong and Myeong-dong were analyzed with both ERAM model and building population weighted ERAM model. The results were analyzed through the correlation test with actual pedestrian population data of the two districts. As a result, the explanation ability of building population weighted ERAM model for the pedestrian population turned out to be higher than the ERAM model. Since building population weighted ERAM model has the structure that can be combined with other weighted ERAM models, it is expected to develop a multi-weighted ERAM model with better explanation ability as a further study.

Microsatellite Markers for Non-Invasive Examination of Individual Identity, Genetic Variation, and Population Differentiation in Two Populations of Korean Long-Tailed Goral (Naemorhedus caudatus)

  • Kim, Baek-Jun
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.3 no.4
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    • pp.191-198
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    • 2022
  • Natural habitats of the Korean long-tailed goral (Naemorhedus caudatus) have been fragmented by anthropogenic activities in South Korea in the last decades. Here, the individual identity, genetic variation, and population differentiation of the endangered species were examined via the multiple-tube approach using a non-invasive genotyping method. The average number of alleles was 3.16 alleles/locus for the total population. The Yanggu population (1.66) showed relatively lower average number of alleles than the Inje population (3.67). Of the total 19 alleles, only seven (36.8%) alleles were shared by the two populations. Using five polymorphic out of six loci, four and six different goral individuals from the captive Yanggu (n=24) and the wild Inje (n=28) population were identified, respectively. The allele distribution was not identical between the two populations (Fisher's exact test: P<0.01). A considerably low migration rate was detected between the two populations (no. of migrants after correction for size=0.294). Additionally, the F statistics results indicated significant population differentiation between them, however, quite low (FST=0.327, P<0.01). The posterior probabilities indicated that the two populations originated from a single panmictic population (P=0.959) and the assignment test results designated all individuals to both populations with nearly equal likelihood. These could be resulted from moderate population differentiation between the populations. No significant evidence supported recent population bottleneck in the total Korean goral population. This study could provide us with useful population genetic information for conservation and management of the endangered species.

Comparative Studies on Genetic Variabilities of Second Chromosomes in Sasang Natural and Experimental Populations of Drosophila melanogaster (자연과 실험집단내 Drosophila melanogaster 제 2 염색체의 유전적 변이성에 대한 비교 연구)

  • Son, Seong-Gon;Choe, Yeong-Hyeon;Lee, Won-Ho
    • Journal of Environmental Science International
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    • v.3 no.4
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    • pp.297-304
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    • 1994
  • The genetic variabilities of second chromosomes concealed Sasang natural and experimental populations of Drosophila melanogaster have been analyzed. The experimental population was composed of D. melanognter which had the lethal-free second chromosome collected from Sasang natural population in 1982. The results were as follow; The mean frequencies of deleterious genes were estimated % be 33.33% in Sasang natural population and 31.72% in experimental population. The allelism rates in lethal genes isolated from the natural and experimental populations were calculated to be about 0.95% and 12.28%, respectively. The allelism rates between lethal genes isolated from the natural population and those of the experimental population were calculated to be about 0.01%. The mean values of elimination by frequencies of deleterious genes and allelism rates were 0.0011 in the natural population and 0.0124 in the experimental population. The frequencies of phenotypic sterility of males in the natural and experimental populations were estimated to be 1.49% and 1.36%, respectively. The frequencies of genotypic sterility of females and males were estimated to be 0.90% and 1.80% in the natural population, and that of males was 2.38% in the experimental population.

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Genetic Variations of Intra- and between-razor Clam Solen corneus Population Identified by PCR Analysis

  • Yoon, Jong-Man
    • Development and Reproduction
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    • v.22 no.2
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    • pp.193-198
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    • 2018
  • The author undertook PCR-founded genetic platform to investigate the hierarchical dendrogram of Euclidean genetic distances of one razor clam population, particularly for Solen corneus, which was further associated with those of the other clam population, by engaging with the precisely designed oligonucleotide primer sets. Seven oligonucleotides primers were used producing a total of 639 counted bands in population A and 595 in population B, respectively, ranging in size of DNA fragments from larger than approximately 50 bp to less than 1,100 bp. Their primers generated 39 specific fragments (6.10%) in population A and 47 (7.90%) in population B, respectively Comparatively, individuals of one razor clam population were fairly related to that of the other clam population, as shown in the hierarchical dendrogram of Euclidean genetic distances. The analysis of genetic variation between razor clam populations could offer important statistics for fisheries and mariculture. Generally the results showed specific and/or conserved genetic loci between razor clam populations. Specific markers established by the author will be valuable for the genetic analysis, species protection and increase of razor clam individuals in coastal region of the Korean Peninsula.

Variation of Shell Color in Three Geographic White Clam ($Meretrix$ $lusoria$) Populations of the Yellow Sea

  • Yoon, Jong-Man;Park, Kyung-Il;Choi, Sang-Hoon
    • Development and Reproduction
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    • v.16 no.1
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    • pp.47-51
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    • 2012
  • Genomic DNAs (gDNAs) were isolated from the hard clam ($Meretrix$ $lusoria$, Roding, 1798) populations of Gunsan located in the Yellow Sea of the Korean peninsula. Genetic distances among different individuals of the LSCP (light shell color population) population of the hard clam (lane 1-11), GSCP (grey shell color population) population of the hard clam (lane 12-22) and DSCP (dark shell color population) population of the hard clam (lane 23-33), respectively, were generated using Systat version 10 according to the bandsharing values and similarity matrix. The dendrogram, generated by seven reliable oligonucleotides primers, indicates 3 genetic clusters. LSCP population could be evidently discriminated with the other two populations among three populations. The longest genetic distance (0.801) was found to exist between individuals in the two populations, between individuals' no. 33 of the DSCP population and no. 06 of the LSCP population. The higher fragment sizes (>2,000 bp) are much more observed in the GSCP population. Three hard clam populations can be clearly distinguished, especially, by their morphological characters and PCR-based approach.