• Title/Summary/Keyword: R linkage

Search Result 247, Processing Time 0.029 seconds

Linkage Disequilibrium and Effective Population Size in Hanwoo Korean Cattle

  • Lee, S.H.;Cho, Y.M.;Lim, D.;Kim, H.C.;Choi, B.H.;Park, H.S.;Kim, O.H.;Kim, S.;Kim, T.H.;Yoon, D.;Hong, S.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.24 no.12
    • /
    • pp.1660-1665
    • /
    • 2011
  • This study presents a linkage disequilibrium (LD) analysis and effective population size ($N_e$) for the entire Hanwoo Korean cattle genome, which is the first LD map and effective population size estimate ever calculated for this breed. A panel of 4,525 markers was used in the final LD analysis. The pairwise $r^2$ statistic of SNPs up to 50 Mb apart across the genome was estimated. A mean value of $r^2$ = 0.23 was observed in pairwise distances of <25 kb and dropped to 0.1 at 40 to 60 kb, which is similar to the average intermarker distance used in this study. The proportion of SNPs in useful LD ($r^2{\geq}0.25$) was 20% for the distance of 10 and 20 kb between SNPs. Analyses of past effective population size estimates based on direct estimates of recombination rates from SNP data demonstrated that a decline in effective population size to $N_e$ = 98.1 occurred up to three generations ago.

Extent of linkage disequilibrium and effective population size of the Landrace population in Korea

  • Shin, Donghyun;Kim, Sung-Hoon;Park, Joowan;Lee, Hak-Kyo;Song, Ki-Duk
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.31 no.8
    • /
    • pp.1078-1087
    • /
    • 2018
  • Objective: The genetic diversity of the Landrace population, a representative maternal pig breed in Korea, is important for genetic improvement. Previously, the effective population size (Ne) has been used to infer the genetic diversity of a population of interest. In this study, we aimed to use single nucleotide polymorphism (SNP) data to characterize linkage disequilibrium (LD) and the Ne of the Korean Landrace population. Methods: We genotyped 1,128 Landrace individuals from three representative Korean major grand-grand-parent (GGP) farms using the Illumina PorcineSNP60 version2 BeadChip, which covers >61,565 SNPs located across all autosomes and mitochondrial and sex chromosomes. We estimated the expected LD and current Ne, as well as ancestral Ne. Results: In the Korean Landrace population, the mean LD ($r^2$) of 3.698 million SNP pairs was $0.135{\pm}0.204$. The mean $r^2$ decreased slowly with as the distance between SNPs increased, and remained constant beyond 3 Mb. According to the $r^2$ calculations, 8,085 of 3.698 million SNP pairs were in complete LD. The current Ne (${\pm}$standard deviation) of the Korean Landrace population is approximately 92.27 [79.46; 105.07] individuals. The ancestral Ne exhibited a slow and steady decline from 186.61 to 92.27 over the past 100 generations. Additionally, we observed more a rapid Ne decrease from the past 20 to 10 generations ago, compared with other intervals. Conclusion: We have presented an overview of LD and the current and ancestral Ne values in the Korean Landrace population. The mean LD and current Ne for the Korean Landrace population confirm the genetic diversity and reflect the history of this pig population in Korea.

Identification of QTLs Associated with Resistance to Riptortus clavatus Thunberg (Heteroptera: Alydidae) in Soybean (Glycine max L. Merr.)

  • Li, Wenxin;Van, Kyujung;Zheng, Da-Hao;Liu, Weixian;Lee, Yeong-Ho;Lee, Sue-Yeon;Lee, Joon-Ho;Lee, Suk-Ha
    • Journal of Crop Science and Biotechnology
    • /
    • v.11 no.4
    • /
    • pp.243-248
    • /
    • 2008
  • The bean bug Riptortus clavatus Thunberg (Heteroptera: Alydidae) is an important pest, causing serious yield loss in soybean. But the information on mechanism of resistance to R. clavatus is limited. The objective of this study was to identify QTLs for R. clavatus resistance using simple sequence repeat (SSR) markers in a soybean population of recombinant inbred lines (RILs) developed from the cross PI 171451 ${\times}$ Hwaeomputkong. A genetic map from this population was constructed with a total of 136 SSR markers covering 1073.9 cM on 20 linkage groups (LGs). With 126 $F_5$ RILs, two independent QTLs for resistance to R. clavatus were mapped on LGs B1 and C2. The amount of phenotypic variation explained by these QTLs ranged from 12 to 16%. PI 171451 showed an escape response to R. clavatus. Under feeding conditions, 14.4% of RILs showed greater resistance to R. clavatus than the resistant parent. The resistance to R. clavatus in soybean from PI 171451 was incomplete and quantitatively inherited and the QTLs for resistance to R. clavatus detected in the RIL population were not significantly affected by epistatic interactions.

  • PDF

A Study on R&D Associations in Korea : Their Development and Future Direction (산업기술연구조합 - 현황과 새로운 발전방향)

  • 김갑수
    • Proceedings of the Technology Innovation Conference
    • /
    • 1999.12a
    • /
    • pp.255-278
    • /
    • 1999
  • R&D association is a very important institution to promote inter-firm technological cooperation, In Korea, they have begun to be established in 1982, and at now 56 R&D associations are working. The purpose of this study is In analyze the problems of the R&D associations, and to suggest a new direction of their future development Their problems were analyzed from the perspective of cooperative R&D mechanisms, especially with a new concept of R&D community : search community, planning community, community of research itself. This study emphases the importance of the R&D association's role as a planning community, and the institutional linkage between R&D association and National R&D program through the introduction of design-in planning system.

  • PDF

Genetic Mapping of Resistant Genes in Brassica pekinensis Against Plasmodiophora brassicae Race 6

  • Lee, Gung-Pyo;Baek, Nam-Kwon;Park, Kuen-Woo
    • The Plant Pathology Journal
    • /
    • v.18 no.5
    • /
    • pp.266-270
    • /
    • 2002
  • Inbred lines of Chinese cabbage KU-101 (resistant line against Plasmodiophora brassicae race race 6) and CS-113 (susceptible line) were crossed and their progeny lines F$_1$, BC$_1$F$_1$, F$_2$, and F$_3$ were produced for the construction of the genetic linkage map of R brassicae race 6-resistant Brassica campestris ssp. pekinensis genome. Restriction fragment length polymorphism (RFLP) was applied to compare between parents and their f$_2$ progenies with a total of 192 probes and 5 restriction enzymes. The constructed RFLP map covered 1,104 cM with a mean distance between genetic marker of 8.0 cM, and produced 10 linkage groups having 121 genetic loci. The loci of P. brassicae race 6 (CR6)-resistant Brassica genome were determined by interval mapping of quan-titative trait loci (QTL), which resulted from bioassay using the same race of the fungi in P3 population. Resistant loci were estimated in numbers 1 (Gl) and 3 (G3) linkage groups. In the regression test, Gl had a value of4.8 logarithm of odd (LOD) score, while C3 had values of 4.2-7.2. Given these results, the location of the CR6-resistant loci within the Brassica genome map can now be addressed.

The Dynamics of University-Industry Linkage: The Case of Mekelle City, Tigray Regional State, Ethiopia

  • Tesfahunegn, Tedros Berhe;Miruts, Gebre
    • STI Policy Review
    • /
    • v.9 no.1
    • /
    • pp.77-98
    • /
    • 2018
  • In the past few decades, the importance of dynamics of University-Industry Linkage(UIL) in strengthening national and regional innovation competency and global competitiveness has been progressively more acknowledged. However, establishing an effective UIL for a better economic development is still a challenging endeavor in Ethiopia, particularly in Tigray region. This study is aimed at assessing the status of UIL and in order to achieve such aim it analyzed the determinants of firms' intensity of interaction with the Mekelle University (MU) and the effect of the intensity of interaction on the relevant firms' innovation performance. The findings of the study showed that the status of UIL between the firms and the university in Tigray region was at an infant stage. The study also found that firm size, firm age (startups) and government supports have had a significant effect on firms' intensity of interaction with the MU. However, the firms' intensity of interaction with the MU did not have any significant effect on the firms' innovation performance. In contrast, cooperation with customers, other groups and suppliers, firm size, firm age, and in-house R&D activities were found to have a significant effect on the firms' innovation performance. In conclusion, the acquisition of knowledge and technology from university does not have an important role in firms' innovation performance in the studied region. Consequently, the government should design effective strategies and assign responsible bodies to implement the strategies, create awareness, and organize both firms and university to meet and work together in order to enhance firms' innovation performance.

Analysis of the oxidized low density lipoprotein receptor 1 gene as a potential marker for carcass quality traits in Qinchuan cattle

  • Gui, Lin-sheng;Raza, Sayed Haidar Abbas;Jia, Jianlei
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.32 no.1
    • /
    • pp.58-62
    • /
    • 2019
  • Objective: The oxidized low density lipoprotein receptor 1 (OLR1) gene plays an important role in the degradation of oxidized low-density lipoprotein and adipocyte proliferation in mammals. For this reason, we aimed at investigating the association of OLR1 gene polymorphisms with carcass quality traits in Chinese Qinchuan cattle. Methods: The single nucleotide polymorphism (SNP) was identified in the 3' untranslated region of bovine OLR1 gene by DNA sequencing. In addition, the haplotype frequency and linkage disequilibrium estimates of three SNPs were evaluated in 520 individuals. Results: Results indicated that the studied three SNPs were within the range of moderate genetic diversity (0.25< polymorphism information content<0.5). Haplotype analysis of three SNPs showed that ten different haplotypes were identified, but only five haplotypes were listed as those with a frequency of <0.05 were excluded. The Hap3 ($-G_1T_2C_3-$) had the highest haplotype frequency (42.10%). Linkage disequilibrium analysis showed that the three SNPs had a low linkage ($r^2<0.001$). The T10588C and C10647T were significantly associated with backfat thickness and intramuscular fat content in Qinchuan cattle. Conclusion: Based on our results, we believe that the OLR1 gene could be a strong candidate gene for influencing carcass quality traits in Qinchuan cattle.

Identification of Quantitative Trait Loci Associated with Traits of Soybean for Sprout

  • Lee, Suk-Ha;Park, Keum-Yong;Lee, Hong-Suk;H. Roger Boerma
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.44 no.2
    • /
    • pp.166-170
    • /
    • 1999
  • The identification of quantitative trait loci (QTL) has the potential to enhance the efficiency of im- proving food processing traits of soybean. In this study, 92 restriction fragment length polymorphism (RFLP) loci and two morphological markers (W$_1$ and T) were used to identify QTL associated with food processing traits of soybean for sprout in 83 F$_2$-derived lines from a cross of 'Pureun' x 'Jinpum 2'. The genetic map consisted of 76 loci which covered about 760 cM and converged into 20 linkage groups. Eighteen markers remained unlinked. Phenotypic data were collected for hypocotyl length, abnormal seedling rate, and sprout yield seven days after seed germination at 2$0^{\circ}C$. Based on the single-factor analysis of variance, eight independent markers were associated with hypocotyl length. Four of seven markers associated with abnormal seedling rate were identified as independent. Seven loci were associated with sprout yield. For three different traits, much of genetic variation was explained by the identified QTL in this population. Several RFLP markers in linkage group (LG) Bl were detected as being associated with three traits, providing a genetic explanation for the biological correlation of sprout yield with hypocotyl length (r=OA07***) and with abnormal seedling rate (r=-406***).

  • PDF

Characteristics and Industrial Linkage of Science Parks : A Case Study of the United Kingdom (영국 과학단지의 특성과 기업연계)

  • 조혜영
    • Journal of the Korean Regional Science Association
    • /
    • v.15 no.1
    • /
    • pp.45-61
    • /
    • 1999
  • A rapid growth of science parks worldwide since 1980s is caused by both the widespread perception that technological innovation is the essential element for the economic development and the notified cases of successful high technology cluster like Silicon Valley. Analyzed in terms of R & D employment and expenditure, new product launches, patent registration, qualifications of the founder, self-rated technological level and the like, the technological level of the science parks in the U.K. reveals very high. While nealy half of the firms on the science parks are represented to be formally linked with universities, the use of the library is referred most frequently among the types of the linkages. R & D links such as contract research, sponsored research, test and analysis were rarely mentioned. Summing up, science parks play an important role for the development of high-tech industries with superior technological characteristics. But in reatlity, there remains so much difference among the individual parks and their location. In addition the individual parks and their location. In addition, institutionalization of the technology transfer with univeristies that only when the science parks are based on the innovative environment they can be successful in the capability of the technological innovation.

  • PDF

A New Model for Connecting the Classification Systems of Knowledge Activities - Linking Research-Technology-Industry and Research-Major-Job - (지식활동의 관계식별을 위한 연계형 분류체계에 관한 연구 - 연구-기술-산업과 연구-전공-취업 연계 -)

  • Seol, Sung-Soo;Song, Choong-Han;Nho, Hwan-Jin
    • Journal of Korea Technology Innovation Society
    • /
    • v.10 no.3
    • /
    • pp.531-554
    • /
    • 2007
  • This paper suggests a new model connecting various knowledge activities through classification systems such as classifications of research, technology, industry, major and job. Although research activities are linked to technology and industry areas or to education and job areas, there is no effort to link these kinds of activities. There are a few studies to link research and technology or research and education respectively. But, there have been no studies to connect technology-industry linkage and education-job linkage. This paper suggests that research area can be a basis of link between technology-industry linkage and education-job linkage. The methods building the links are not simple, but easy; 1) setting up new science/research classification system having two dimensions of research and application, 2) building electronic systems and databases allowing fields for several classification systems, and 3) making rules using multi-dimensional classification systems following the purpose of the programs. The model is designed to meet the needs of nationwide R&D and human resources policies, and for the preparation of knowledge society to grasp the relationship between sequential activities using knowledge. If we know the interactive relationships between various areas, we can trace related phenomena in different activities with restricted information.

  • PDF