• International Journal of Human Ecology
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• v.11 no.2
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• pp.15-23
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• 2010

This study explored genetic and environmental contributions to optimism, depressive symptoms, and the association between the two using a genetically informative sample from the Nonshared Environment and Adolescent Development project (NEAD: D. Reiss; J. M. Neiderhiser; E. M. Hetherington; & R. Plomin, 2000. At Time 1 of the longitudinal NEAD study, the sample consisted of 720 samesex twins and sibling pairs from two parent families. The study used parent, adolescent, and observer ratings of depressive symptoms as well as adolescent ratings of optimism. The results revealed that genetic influences explained approximately half of the variability in optimism and depressive symptoms. Nonshared environmental influences also substantially contributed to optimism and depressive symptoms. Bivariate genetic analyses (which partitioned the covariance between optimism and depressive symptoms into genetic and environmental components) indicated that genetic influences accounted for a moderate percentage of the association.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1355-1359
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• 2004

Japanese Black cattle of Hyogo prefecture (Tajima strain) are famous for its ability to produce high-quality meat and have been maintained as a closed system for more than 80 years. In order to assess the usefulness of microsatellite markers in closed cattle populations, and evaluate the genetic structure of the Tajima strain, we analyzed representative dams of the Tajima strain comprised of the substrains Nakadoi and Kinosaki. Genetic variability analyses indicated low genetic diversity in the Tajima strain. In addition, a recent genetic bottleneck, which could be accounted for by the high level of inbreeding, was detected in both substrains. In phylogenetic analyses, relationship coefficients and genetic distances between individuals were calculated using pedigree and microsatellite information. Two phylogenetic trees were constructed from microsatellite and pedigree information using the UPGMA method. Both trees illustrated that most individuals were distinguished clearly on the basis of the two substrains, although in the microsatellite tree some individuals appeared in clusters of different substrains. Comparing the two phylogenetic trees revealed good consistency between the microsatellite analysis tree and the pedigree information. The correlation coefficient between genetic distances derived from microsatellite and pedigree information was 0.686 with a high significance level (p<0.001). These results indicated that microsatellite information may provide data substantially equivalent to pedigree information even in unusually inbred herds of cattle, and suggested that microsatellite markers may be useful in revealing genetic structure without accurate or complete pedigree nformation. Japanese Black cattle of Hyogo prefecture (Tajima strain) are famous for its ability to produce high-quality meat and have been maintained as a closed system for more than 80 years. In order to assess the usefulness of microsatellite markers in closed cattle populations, and evaluate the genetic structure of the Tajima strain, we analyzed representative dams of the Tajima strain comprised of the substrains Nakadoi and Kinosaki. Genetic variability analyses indicated low genetic diversity in the Tajima strain. In addition, a recent genetic bottleneck, which could be accounted for by the high level of inbreeding, was detected in both substrains. In phylogenetic analyses, relationship coefficients and genetic distances between individuals were calculated using pedigree and microsatellite information. Two phylogenetic trees were constructed from microsatellite and pedigree information using the UPGMA method. Both trees illustrated that most individuals were distinguished clearly on the basis of the two substrains, although in the microsatellite tree some individuals appeared in clusters of different substrains. Comparing the two phylogenetic trees revealed good consistency between the microsatellite analysis tree and the pedigree information. The correlation coefficient between genetic distances derived from microsatellite and pedigree information was 0.686 with a high significance level (p<0.001). These results indicated that microsatellite information may provide data substantially equivalent to pedigree information even in unusually inbred herds of cattle, and suggested that microsatellite markers may be useful in revealing genetic structure without accurate or complete pedigree information.

• Journal of Ginseng Research
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• v.42 no.2
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• pp.158-164
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• 2018

Background: The study was carried out to assess the genetic variability present in ashwagandha and to examine the nature of associations of various traits to the root yield of the plant. Methods: Fifty-three diverse genetic stocks of ashwagandha (Withania somnifera) were evaluated for 14 quantitative characteristics. Analysis of variance, correlation, and path coefficient analysis were performed using the mean data of 2 years. Results: Analysis of variance revealed that the genotypes differed significantly for all characteristics studied. High heritability in conjunction with high genetic advance was observed for fresh root weight, 12 deoxywithastramonolide in roots, and plant height, which indicated that selection could be effective for these traits. Dry root weight has a tight linkage with plant height and fresh root weight. Further, in path coefficient analysis, fresh root weight, total alkaloid (%) in leaves, and 12 deoxywithastramonolide (%) in roots had the highest positive direct effect on dry root weight. Conclusion: Therefore, these characteristics can be exploited to improve dry root weight in ashwagandha genotypes and there is also scope for the selection of promising and specific chemotypes (based on the alkaloid content) from the present germplasm.

• The Korean Journal of Malacology
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• v.25 no.1
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• pp.5-13
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• 2009

Genomic DNA isolated from two geographical ark shell (Scapharca subcrenata) populations was amplified several times by PCR reactions. The ark shell population from Daecheon (ASPD) and from Wonsan (ASPW) in the West Sea and the East Sea of Korean Peninsula, respectively, obtained. The seven arbitrarily selected primers OPA-05, OPA-11, OPB-09, OPB-11, OPB-14, OPC-18 and OPD-07 were shown to generate the loci observed per primer, shared loci by each population, specific loci, unique shared loci to each population and shared loci by the two populations which could be clearly scored. Here, 862 loci were identified in the ASPD population, and 1,191 in the ASPW population: 137 specific loci (15.9%) in the Daecheon population and 84 (7.1%) in the Wonsan population. 407 shared loci by each population, with an average of 58.1 per primer, were observed in the ASPD population. 473 shared loci by each population, with an average of 67.6 per primer, were identified in the ASPW population. The numbers of specific loci in the ASPD and ASPW population were 137 and 84, respectively. Consequently, the average bandsharing value of individuals within the ASPW population was much higher than in the ASPD population. The bandsharing value between individuals' no. 08 and no. 13 was 0.628, which was the highest measured between the two geographical populations. The dendrogram obtained by the seven primers indicated three genetic clusters: cluster 1 (DAECHEON 01-DAECHEON 11), cluster 2 (WONSAN 12 and 14) and cluster 3 (WON SAN 13, 15, 16, 17, 18, 19, 20, 21 and 22). The genetic distance between the two geographical populations ranged from 0.043 to 0.499. Especially, individual no. 10 of Daecheon population was most distantly related to no. 14 of Wonsan population (genetic distance = 0.499).

• Journal of Korean Society of Forest Science
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• v.94 no.2 s.159
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• pp.73-81
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• 2005

This study was conducted to examine the geographic variation among provenances of Pinus densiflora in survival rate and height growth at four test plantations (Jungsun, Chungju, Naju, and Jeju). The plantations were parts of the eleven provenance trials of Pinus densiflora established by Korea Forest Research Institute in 1996. The survival rate and height growth were significantly different among test plantations at $p{\leq}0.01$. Latitude and longitude of test plantation were negatively correlated with survival rate and height growth. On the other hand, annual mean temperature, mean temperature (Nov.~Feb.), extremely low temperature (Dec.~Feb.), and annual mean growing days of test plantation were positively correlated with these two. The relationships between growth variables and geographic variables were analysed with canonical correlation analysis. A considerable amount of variation in survival rate and height growth was explained by latitude, annual mean growing days, extremely low temperature (Dec.~Feb.) and extremely high temperature (Nov.~Feb.) of provenances. It is estimated that up to 47.1% and 67.4% of the genetic variability in survival rate and height growth was attributable to the environmental variability of the provenances, respectively. The response surface curve of survival rate and height growth was plotted against latitude and longitude to examine growth performance of provenances for each test site. Generally, the local provenances showed better survival rate and height growth.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.273-278
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• 2005

Trifolium pratense (red clover, Fabaceae) is a short-lived herbaceous species and the species is introduced from Europe or North America to Korea approximately 60 years ago. Allozyme variability was examined in populations representing this species. A high level of genetic variation was found in T. pratense populations. Ten of 19 loci $(52.6\%)$ showed detectable polymorphism. Genetic diversity was 0.220. The sexual reproduction, high fecundity, and colonization process are proposed as possible factors contributing to high genetic diversity. Genetic diversity (0.220) was lower than that (0.285) of North American red clover, T. pratense. Korean populations of red clover may be founded by a small sample of larger or moderate populations. An indirect estimate of the number of migrants per generation (Nm = 4.20) indicated that gene flow was extensive among Korean populations of this species.

• Horticulture, Environment, and Biotechnology : HEB
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• v.59 no.6
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• pp.875-888
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• 2018

Tulip (Tulipa L.) is one of the most important ornamental geophytes in the world. Analysis of molecular variability of tulips is of great importance in conservation and parental lines selection in breeding programs. Of the 70 genic microsatellites, 15 highly polymorphic and reproducible markers were used to assess the genetic diversity, structure, and relationships among 280 individuals of 36 wild and cultivated tulip accessions from two countries: Iran and the Netherlands. The mean values of gene diversity and polymorphism information content were 0.69 and 0.66, respectively, which indicated the high discriminatory power of markers. The calculated genetic diversity parameters were found to be the highest in wild T. systola Stapf (Derak region). Bayesian model-based STRU CTU RE analysis detected five gene pools for 36 germplasms which corresponded with morphological observations and traditional classifications. Based on analysis of molecular variance, to conserve wild genetic resources in some geographical locations, sampling should be performed from distant locations to achieve high diversity. The unweighted pair group method with arithmetic mean dendrogram and principal component analysis plot indicated that among wild tulips, T. systola and T. micheliana Hoog exhibited the closest relationships with cultivated tulips. Thus, it can be assumed that wild tulips from Iran and perhaps other Middle East countries played a role in the origin of T. gesneriana, which is likely a tulip species hybrid of unclear origin. In conclusion, due to the high genetic variability of wild tulips, they can be used in tulip breeding programs as a source of useful alleles related to resistance against stresses.

• The Plant Pathology Journal
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• v.23 no.2
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• pp.45-50
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• 2007

Genetic diversity among selected isolates of Macrophomina phaseolina, a causal agent of charcoal rot (stalk rot) disease in sorghum was studied using PCR-RAPD markers. A set of ten isolates, from ten different rabi sorghum genotypes representing two traditional sorghum growing situations viz., Dharwad- a transitional high rainfall region and Bijapur- a semi-arid low rainfall region in South India. From a set of 40 random primers tested, amplicon profiles of 15 were reproducible. A total of 149 amplicon levels, with an average of 9.9 bands per primer, were available for analysis, of which 148 were polymorphic (99.3%). It was possible to discriminate all the isolates with any of the 15 primers employed. UPGMA clustering of data indicated that the isolates shared varied levels of genetic similarity within a range of 0.14 to 0.72 similarity coefficient index and it was suggestive that grouping of isolates was not related to sampling location in anyway. A high level of genetic heterogeneity of 0.28 was recorded among the isolates.

• Korean Journal of Veterinary Service
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• v.25 no.1
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• pp.97-103
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• 2002

Infectious bronchitis(IB) is a viral disease in which continued evolution of the virus is of paramount importance for annual endemics and epidemics in chickens. Since the isolation of IB viruses(IBVs) in the 1930s, over 50 serotypes or variants have been reported worldwide. Continuing evolution is most prominent in the suface glycoproteins of IBV but also occurs in other parts of the genome. This genetic variability results from accumulation of molecular changes that can occur by a number of different mechanisms including genetic drift (point mutations) and genetic shift(RNA recombination). GA98 is a new serotype of IBV identified recently in the United States. In this paper, the evolutionary trend of IBV will be discussed using GA98 serotype as a model.

• Genomics & Informatics
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• v.9 no.2
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• pp.45-51
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• 2011

How personality forms and whether personality genes exist are long-studied questions. Various concepts and theories have been presented for centuries. Personality is a complex trait and is developed through the interaction of genes and the environment. Twin and family studies have found that there are critical genetic and environmental components in the inheritance of personality traits, and modern advances in genetics are making it possible to identify specific variants for personality traits. Although genes that were found in studies on personality have not provided replicable association between genetic and personality variability, more and more genetic variants associated with personality traits are being discovered. Here, we present the current state of the art on genetic research in the personality field and finally list several of the recently published research highlights. First, we briefly describe the commonly used self-reported measures that define personality traits. Then, we summarize the characteristics of the candidate genes for personality traits and investigate gene variants that have been suggested to be associated with personality traits.