• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제2권2호
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• pp.108-113
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• 2021

Detrimental effects of inbreeding have been studied by many researchers for a long time. However, only a few studies have shown the occurrence of inbreeding depression due to evolutionary changes as a purging process. In this study, two different populations (inbreeding and outbreeding) of Drosophila melanogaster were compared to assess inbreeding effects on artificial population bottlenecks. For inbreeding conditions, a couple of D. melanogaster (one virgin and one male) were selected from an inbred population and cultured in a vial. For outbreeding conditions, a couple of D. melanogaster were selected from different populations and cultured in a vial. There were significant differences in body lengths of adults, but not in other parameters such as the total number of adults, the rate of survival, and the rate of wing mutants. The mean body length of adults of outbreeding populations was longer than that of inbreeding populations in the first generation (G1; P = 0.004), but not in the second generation (G2; P = 0.066). Although the other three parameters (total number of adults, rate of survival, and rate of wing mutants) showed differences in their mean values between inbreeding and outbreeding populations, these differences were not statistically significant. This might be due to genetic purging. This study demonstrated one additional experimental case related to inbreeding depression in artificial bottlenecked populations. Further studies are necessary to confirm the clear interaction between inbreeding depression and genetic purging using more generations and replicates (or samples) of D. melanogaster.

• 식물분류학회지
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• 제53권1호
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• pp.14-24
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• 2023

Saussurea dorogostaiskii Palib. (Asteraceae) is a critically endangered medicinal plant in Mongolia and Russia. We studied the genetic variation of S. dorogostaiskii from three mountains of northern Mongolia. The genetic profile was assessed in 70 individuals from eight populations using five inter-simple sequence repeat markers, producing 53 loci with 96.4% polymorphism across all bands. Shannon's index (I) and Nei's gene diversity (H) value at the species level of S. dorogostaiskii are 0.25 and 0.17, respectively. An AMOVA showed high genetic variation among the populations (22% of populations and 32% of mountains), consistent with the high genetic differentiation (G_ST = 0.49) and low gene flow (N_m = 0.51) in S. dorogostaiskii populations. Eight populations were clustered into two groups, corresponding to their geographic locations. The low within-population genetic diversity and high genetic differentiation among S. dorogostaiskii populations factor into their endangered designation. This genetic analysis reveals that all populations are equally threatened, and community-based conservation is appropriate for these species.

• 한국자원식물학회지
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• 제20권4호
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• pp.336-341
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• 2007

우리나라의 대표적 향토수종인 소나무 침엽의 지리적 변이를 알아보기 위하여 남한 전 지역을 대상으로 위도와 경도를 30' 간격으로 교차되는 35집단을 선정하고 침엽을 채취하여 형태적 특성을 조사하였다. 침엽길이, 침엽폭, 기공열수, 기공밀도, 거치수, 수지구수가 집단간, 개체간에 많은 차이가 있었으며, 개체간의 차이가 집단간의 차이보다 더 컸다. 기공밀도는 남부지역의 집단들 보다는 북부지역의 집단들이 더 높았으며, 표고가 낮은 지역의 집단들 보다는 표고가 높은 지역의 집단들이 기공밀도가 더 높았다. 거치수는 북부지역의 집단들보다는 남부지역의 집단들이 더 많았으며, 표고가 높은지역의 집단들보다는 표고가 낮은 지역의 집단들이 더 많았다. 수지구 수는 해안에서 거리가 먼 내륙의 집단들 보다는 해안에서 거리가 가까운 집단들이 더 많았다. 그리고 수지구 지수는 동부지역의 집단들 보다는 서부지역의 집단들이 더 높았다. 침엽의 형태적 특성으로 유집분석 결과 3개 군으로 구분되었으며 제III군은 I, II군에 비하여 거치수는 적고, 기공 밀도가 높은 태백산맥 주위의 집단들이었다.

• 천문학논총
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• 제25권3호
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• pp.91-99
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• 2010

An increasing number of observations have confirmed the presence of multiple stellar populations in Galactic globular clusters. Multiple populations evidence come from the complex chemical pattern of stars hosted in GCs and from the split or broadening of different evolutionary sequences in the color-magnitude diagrams. Multiple stellar populations have been identified in Galactic and Magellanic Cloud clusters, as well as in external galaxies. In this paper I will summarize the observational facts.

• Journal of Animal Science and Technology
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• 제53권1호
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• pp.35-42
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• 2011

초위성체(MS) 표지를 이용하여 한국재래돼지 집단의 각각의 분자유전학적 특성을 조사하고 그 평가를 통해 한국재래돼지에 대한 품종 및 계통분류의 기초를 마련하고자 본 연구를 수행하였다. 또한, 각 재래돼지 집단 내 및 집단간의 유전적 변이성을 확인하고, 그 분류 및 특성평가를 위한 MS 분석체계를 마련하여 국내 가축 유전자원 관리에 활용하고자 하였다. 국내 관리기관 및 농가에서 보유하고 있는 6개 재래돼지 집단을 중국의 4개 재래돼지 집단 및 외래종 돼지 7개 집단과 함께 분석하였다. 도합 17집단 648두를 대상으로 26개 MS 표지로 분석한 결과, 한국재래돼지 집단은 외래종과 중국재래돼지로부터 분자유전학적으로 별개의 집단으로 확연히 구분되는 것을 확인하였다. 한국재래돼지 집단의 기대이형접합도($H_E$)는 0.65의 값을 보인 두 집단(B, D)을 제외한 나머지에서 0.48~0.55의 수준을 보여 전반적으로 외래종에 비해 낮았다. 한국재래돼지 집단간의 유전거리 또한 0.12~0.34 정도로 비교대상에 비하여 낮았다. 분석대상 한국재래돼지 6집단 중 세 개의 집단은 높은 유전적 균일도를 보였으나, 두 집단에서는 일부 집단의 혼입을, 나머지 하나의 집단에서는 둘 이상의 집단으로부터의 복잡한 혼입이 의심되는 매우 낮은 유전적 균일도를 확인하였다. 본 연구를 통하여 한국재래돼지 집단간의 유전적 차이 및 동질성, 그리고 집단내의 유전적 균일성을 확인하였다. 이러한 결과는 국내유전자원의 고유성을 인정할 수 있는 과학적인 근거로서, 국가수준의 가축유전자원 평가, 관리의 기초자료로 활용될 수 있을 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1223-1228
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• 2012

The population sizes of three Korean indigenous cattle populations have been drastically reduced over the past decades. In this study, we examined the extent to which reduction in populations influenced genetic diversity, population structure and demographic history using complete mitochondrial DNA (mtDNA) control region sequences. The complete mtDNA control region was sequenced in 56 individuals from Korean Black (KB), Jeju Black (JEB) and Korean Brindle (BRI) cattle populations. We included 27 mtDNA sequences of Korean Brown (BRO) from the GenBank database. Haplotype diversity estimate for the total population was high (0.870) while nucleotide diversity was low (0.004). The KB showed considerably low nucleotide (${\pi}$ = 0.001) and haplotype (h = 0.368) diversities. Analysis of molecular variance revealed a low level of genetic differentiation but this was highly significant (p<0.001) among the cattle populations. Of the total genetic diversity, 7.6% was attributable to among cattle populations diversity and the rest (92.4%) to differences within populations. The mismatch distribution analysis and neutrality tests revealed that KB population was in genetic equilibrium or decline. Indeed, unless an appropriate breeding management practice is developed, inbreeding and genetic drift will further impoverish genetic diversity of these cattle populations. Rational breed development and conservation strategy is needed to safeguard these cattle population.

• Journal of Plant Biotechnology
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• 제39권1호
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• pp.75-80
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• 2012

$Kalopanax$ $pictus$ is a long-lived deciduous perennial tree in the family Araliaceae mainly distributed in the East Asia. In Korea, this species is of ecological and medical importance. Because typical populations of this species are small and distributed in patches, $K.$ $pictus$ has been considered as a narrow habitat species. To understand the genetic diversity and population structure of this species, the sequence variation of the nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) region was analyzed among 18 different $K.$ $pictus$ populations in the present investigation. The nrDNA ITS sequences of Korean populations investigated in this study showed identical of 616 bp in length, and no any nucleotide variation was found in the entire nrDNA ITS region sequence. This result suggested that the $K.$ $pictus$ populations in Korea might belong to the same isolate, and no mutation was found in the nrDNA ITS region. Compared with other known ITS sequence sources from $K.$ $pictus$ populations, only four variable nucleotide sites were found within the entire ITS region. Very narrow genetic diversity appearing in the population level of $K.$ $pictus$ makes us hypothesize that their relatively isolated habitats. The long-lived traits might be one main reason. However, another probability was that the nr-DNA ITS region might be noneffective in classifying populations of $K.$ $pictus$. Thus, to further understand the phylogenetic relationship of $K.$ $pictus$ populations, more samplings should be performed based on more DNA sequences.

• Asian-Australasian Journal of Animal Sciences
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• 제21권12호
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• pp.1710-1720
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• 2008

A comprehensive genome profiling study was undertaken based on automated genotyping and analysis of 20 microsatellite markers that involved 155 birds representing eight different populations. The distribution of microsatellite markers in each of these breeds helped us to decipher genetic heterogeneity, population genetic structure and evolutionary relationships of the present day chicken populations in India. All the microsatellite loci utilized for the analysis were polymorphic and reasonably informative. A total of 285 alleles were documented at 20 loci with a mean of 14.25 alleles/locus. A total of 103 alleles were found to be population/strain specific of which, only 30 per cent had a frequency of more than 10. The mean PIC values ranged from 0.39 for the locus ADL158 to 0.71 for loci MCW005 or ADL267 across the genomes and 0.55 in Dahlem Red to 0.71 in Desi (non-descript), among the populations. The overall mean expected and observed heterozygosity estimates for our populations were 0.68 and 0.64, respectively. The overall mean inbreeding coefficients (FIS) varied between -0.05 (Babcock) and 0.16 (Rhode Island Red). The pairwise FST estimates ranged from 0.06 between Aseel and Desi (non-descript) to 0.14 between Dahlem Red and Babcock. The Nei's genetic distance varied from 0.30 (WLH-IWD and WLH-IWF) to 0.80 (Dahlem Red and Babcock. Phylogenetic analysis grouped all the populations into two main clusters, representing i) the pure breeds, Dahlem Red and Rhode Island Red, and ii) the remaining six populations/strains. All the chicken populations studied were in the state of mild to moderate inbreeding except for commercial birds. A planned breeding is advised for purebreds to revive their genetic potential. High genetic diversity exists in Desi (non-descript), local birds, which can be exploited to genetically improve the birds suitable for backyard poultry.

• 한국자원식물학회지
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• 제24권5호
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• pp.540-548
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• 2011

고로쇠나무 11개 자연집단의 잎의 14가지 형태적 특성에 대한 변이분석을 실시하였다. Nested 분산분석 결과 14가지 양적특성들 모두에서 집단간 및 집단 내 개체 간에 유의적인 차이를 보였으며, 모든 형질들에서 총 분산 가운데 집단 내 개체 간 차지하는 비율이 집단간 차지하는 비율보다 큰 것으로 나타났다. 집단간 분화정도를 알아보고 형질간 상호비교를 위하여 표준화시킨 $D_{ij}$값은 엽신장/엽병장(0.90), 상열편폭(0.85) 및 엽신장과 중열편폭(0.83) 특성들이 다른 형질들에 비해 이탈정도가 큰 형질들로 나타났다. 또한 14가지 형태적 특성에 대한 전체평균 $D_{ij}$값은 광양(1.36)과 청양(1.30) 집단이 집단분화가 가장 큰 값을 보인반면 울주(0.30)와 정선(0.44) 집단이 가장 작은 값을 보여 조사된 집단들 중 울주와 정선집단이 고로쇠나무 잎의 형태적 특성을 대표할 수 있는 평균집단에 가까운 것으로 나타났다.

• Journal of Ecology and Environment
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• 제30권1호
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• pp.57-62
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• 2007

To obtain demographic information on threatened gold-spotted pond frog (Rana chosenica Okada, 1931) populations, we determined the ages of 45 male and 13 female frogs (20 males and 9 females from Cheongwon and 25 males and 4 females from Tae-an) and compared the age structures and growth patterns of the two populations in 2006. The snout-vent length (SVL) and body weight of female frogs were greater than those of male frogs in both populations. Male frogs' ages ranged 2 to 7 years old and females' ages ranged 3 to 6 years old. In both populations, 4 years old male frogs were the most abundant age-sex class. The age structures of the two populations were significantly different and the growth coefficients of male frogs from the Cheongwon population were greater than those from the Tae-an population. The mean age of males from the Tae-an population was higher than that from the Cheongwon population. However, the SVL and body weights of male frogs were not different between two populations and there was no difference between the two populations in the mean male SVL at any age. The results could increase our understanding of the life-history of this threatened frog and may be useful in conservation planning.