• Title/Summary/Keyword: Genetic effects

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Effect of Glycine on L-Ornithine Production by a Citrulline Auxotroph of Brevibacterium ketoglutamicum and Stoichiometric Analysis

  • Nam, Soo-Wan;Choi, Dae-Keon;Ryu, Wuk-Sang;Jang, Hyung-Wook;Chung, Bong-Hyun;Park, Young-Hoon
    • Journal of Microbiology and Biotechnology
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    • 제4권2호
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    • pp.95-101
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    • 1994
  • The effects of glycine on cell growth and L-omithine production were investigated in shake-flask and jar fermentor cultures of a citrulline auxotrophic mutant, Brevibacterium ketoglutamicum BK 1046. In the shake-flask culture, the optimal concentration of glycine for L-ornithine production was found to be 20 g/l. In the jar fermentor culture with the glycine at an initial concentration of 20 g/l, L-ornithine production increased by 28%, compared to that of the culture with no glycine added. 37 g/l of L-ornithine was produced when additional feeding of glycine (5 g/l) was made. This was a significant improvement in L-ornithine production compared to that (ca. 24 g/l) of the corresponding batch culture conducted without glycine. According to the stoichiometric analysis with the batch fermentation results, the experimental and theoretical L-ornithine yields based on the glucose consumption were 0.24 and 0.59, respectively. This indicates that the performance of L-ornithine fermentation can further be improved by the supplementation of glycine and the development of a mutant strain possessing a higher growth yield.

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임상유전학 교육에서 새로운 교과과정 개발의 필요성 (The Need for a New Curriculum in Clinical Genetic Education)

  • 이창우
    • 의학교육논단
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    • 제16권1호
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    • pp.50-54
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    • 2014
  • It is becoming increasingly important for medical doctors to have a thorough understanding of human genetics and the ethical, legal, and social implications of genetic testing, counseling, and treatment. As genetic engineering and technology evolves, medical doctors will find themselves called in to counsel patients about a rapidly increasing number of diseases for which genetic testing and treatments are available. Medical doctors will need to master a new set of principles and clinical skills. A lack of knowledge about these issues and problems may lead to serious, lifelong or even fatal negative effects on patients. Medical genetics has moved from the study of rare conditions to the illumination of disorders that impact the entire spectrum of medical practice. This study demonstrates several areas in which medical genetics is clearly an important tool in medical practice and the necessity of establishing new curriculum for clinical genetic education in Korea. Medical students nearing graduation may lack genetic knowledge that is essential for daily practice because genetics has little or no place in clinical teaching. Medical schools should make extensive curriculum changes to increase students' awareness of clinical genetics and its ethical implications. The medical school curriculum will need creative new approaches to keeping up with the rapid pace of evolution of clinical genetics.

A Preliminary Population Genetic Study of an Overlooked Endemic ash, Fraxinus chiisanensis in Korea Using Allozyme Variation

  • Lee, Heung Soo;Chang, Chin-Sung;Kim, Hui;Choi, Do Yeol
    • 한국산림과학회지
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    • 제98권5호
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    • pp.531-538
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    • 2009
  • We used enzyme electrophoresis to evaluate genetic diversity in five populations of endemic ash, Fraxinus chiisanensis in Korea. Of 15 putative allozyme loci examined 26.7% were polymorphic and expected heterozygosity for the species was low (0.082). Within the range, population were highly differentiated ($F_{ST}$=0.356) and little genetic variation was explained by geography. The pattern of distribution of variation showed low genetic variation within populations and pronounced divergence among populations, which was consistent with the prediction for the effects of limited gene flow and local genetic erosion. Although the frequencies of male plants were dominant ranging from 79.3% to 89.4%, most mating events seems to be inevitable mating between relatives in small populations based on heterozygote deficiency of this species. Small effective population size and the limited dispersal contributed to the low rates of gene flow within as well as between populations.

Heritabilities and Genetic Correlation, and Sire and Environment Effects on Meat Production Potential of Hanwoo Cattle

  • Baik, D.H.;Hoque, M.A.;Park, G.H.;Park, H.K.;Shim, K.S.;Chung, Y.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권1호
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    • pp.1-5
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    • 2003
  • Genetic parameters of live weight at slaughter (LWT), quantity index (QIX), yield grade (YGD), quality grade (QGD), pH of meat, and boiled meat tenderness in terms of mastication (BMAS), shear force (BSFR) and penetration (BPEN) in Hanwoo steers were estimated. Effects of sire, location and their interaction on these traits were also evaluated. Sire effects were found to be significant on all the traits studied except for pH and BSFR. The LWT, QIX and QGD were also significantly affected both by location and by interaction effect between sire${\times}$location. The BSFR and BPEN were significantly (p<0.01) affected by location but not significantly by sire${\times}$location interaction. The boiled meat tenderness and pH were negatively correlated ($r_g$ and $r_p$) with LWT, QIX and QGD. All the other traits were positively correlated with each other. Positive and high genetic correlation (+0.56) between LWT and QGD was obtained indicating that selection for LWT would improve QGD. The $h^2$ estimates were 0.43, 0.37, 0.37, 0.35 and 0.32 for QGD, LWT, pH, BSFR and BPEN, respectively.

Confirmation of genotypic effects for the bovine APM1 gene on marbling in Hanwoo cattle

  • Kwon, Anam;Srikanth, Krishnamoorthy;Lee, Eunjin;Kim, Seonkwan;Chung, Hoyoung
    • Journal of Animal Science and Technology
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    • 제58권4호
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    • pp.15.1-15.6
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    • 2016
  • Background: Our previous study had identified the SNP (g.81966377T > C) and indel (g.81966364D > I) located in the promoter of APM1 to have a significant effect on marbling in Hanwoo. APM1 encodes an adipocytokine called adiponectin, which plays a significant role in lipogenesis. The aim of this study was to verify and validate the effect of the SNP and indel on marbling and other carcass traits in a large, representative, countrywide population of Hanwoo cattle. The carcass traits measured were marbling (MAR), backfat thickness (BFT), loin eye area (LEA), and carcass weight (CAW). Results: Primers were designed to amplify 346 bp of the genomic segment that contained the targeted SNP (g.81966377) and the indel (g.81966364). After data curation, the genotypes of 8,378 individuals identified using direct sequencing analysis estimated frequencies for C (0.686) and T (0.314) respectively showing genotype frequencies for CC (0.470), CT (0.430) and TT (0.098). The genotypes were significantly associated with MAR, BFT and LEA. The indel had significant effect on marbling (P < .0001) with strong additive genetic effects. The allele frequencies was estimated at (DEL, 0.864) and insertion (INS, 0.136) presenting genotypes of D/D (75.63 %), D/I (21.44 %), and I/I (2.92 %). Significant departure from Hardy-Weinberg equilibrium was not detected for both the SNP and the indel. Conclusion: The SNP genotypes showed significant association with MAR, BFT and LEA with strong additive genetic effects, while the indel was significantly associated with MAR. The results confirmed that the variants can be used as a genetic marker for improving marbling in Hanwoo.

Meta-analysis of Association Studies of CYP1A1 Genetic Polymorphisms with Digestive Tract Cancers Susceptibility in Chinese

  • Liu, Chang;Jiang, Zheng;Deng, Qian-xi;Zhao, Ya-nan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권11호
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    • pp.4689-4695
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    • 2014
  • Background: A great number of studies have shown that cytochrome P450 1A1 (CYP1A1) genetic polymorphisms, CYP1A1 Msp I and CYP1A1 Ile/Val, might be risk factors for digestive tract cancers, including esophageal cancer (EC), gastric cancer (GC), hepatic carcinoma (HC), as well as colorectal cancer (CC), but the results are controversial. In this study, a meta-analysis of this literature aimed to clarify associations of CYP1A1 genetic polymorphisms with digestive tract cancers susceptibility in Chinese populations. Materials and Methods: Eligible case-control studies published until December 2013 were retrieved by systematic literature searches from PubMed, Embase, CBM, CNKI and other Chinese databases by two investigators independently. The associated literature was acquired through deliberate search and selection based on established inclusion criteria. Fixed-effects or random-effects models were used to estimate odds ratios (ORs and 95%CIs). The meta-analysis was conducted using Review Manager 5.2 and Stata 12.0 softwares with stability evaluated by both stratified and sensitivity analyses. Moreover, sensitivity analysis and publication bias diagnostics confirmed the reliability and stability. Results: Eighteen case-control studies with 1,747 cases and 2,923 controls were selected for CYP1A1 MspI polymorphisms, and twenty case-control studies with 3, 790 cases and 4, 907 controls for the CYP1A1 Ile/Val polymorphisms. Correlation associations between CYP1A1 Ile/Val polymorphisms and digestive tract cancers susceptibility were observed in four genetic models in the meta-analysis (GG vs AA:OR= 2.03, 95%CI =1.52- 2.72; AG vs AA: OR=1.26, 95%CI =1.07-1.48; [GG+AG vs AA] :OR =1.42, 95%CI=1.20-1.68, [GG vs AA+AG]:OR=1.80, 95%CI =1.40-2.31). There was no association between CYP1A1 Msp I polymorphisms and digestive tract cancers risk. Subgroup analysis for tumor type showed a significant association of CYP1A1 Ile/Val genetic polymorphisms with EC in China. However, available data collected by the study failed to reveal remarkable associations of GC or HC with CYP1A1 Ile/Val genetic polymorphisms and EC, GC or CC with CYP1A1 MspI genetic polymorphisms. Conclusions: Our results indicated that CYP1A1 Ile/Val genetic polymorphisms, but not CYP1A1 Msp I polymorphisms, are associated with an increased digestive tract cancers risk in Chinese populations. Additional well-designed studies, with larger sample size, focusing on different ethnicities and cancer types are now warranted to validate this finding.

American Ginseng: Research Developments, Opportunities, and Challenges

  • Punja, Zamir K.
    • Journal of Ginseng Research
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    • 제35권3호
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    • pp.368-374
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    • 2011
  • American ginseng (Panax quinquefolius L.) is grown in some regions of the USA and Canada and marketed for its health promoting attributes. While cultivation of this plant species has taken place in North America for over 100 years, there are many challenges that need to be addressed. In this article, the current production method used by growers is described and the challenges and opportunities for research on this valuable plant are discussed. These include studies on pharmacological activity, genetic diversity within the species, genetic improvement of currently grown plants, molecular characterization of gene expression, and management of diseases affecting plant productivity. The current research developments in these areas are reviewed and areas requiring further work are summarized. Additional research should shed light on the nature of the bioactive compounds and their clinical effects, and the molecular basis of active ingredient biosynthesis, and provide more uniform genetic material as well as improved plant growth, and potentially reduce losses due to pathogens.

Optimum design of composite steel frames with semi-rigid connections and column bases via genetic algorithm

  • Artar, Musa;Daloglu, Ayse T.
    • Steel and Composite Structures
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    • 제19권4호
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    • pp.1035-1053
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    • 2015
  • A genetic algorithm-based minimum weight design method is presented for steel frames containing composite beams, semi-rigid connections and column bases. Genetic Algorithms carry out optimum steel frames by selecting suitable profile sections from a specified list including 128 W sections taken from American Institute of Steel Construction (AISC). The displacement and stress constraints obeying AISC Allowable Stress Design (ASD) specification and geometric (size) constraints are incorporated in the optimization process. Optimum designs of three different plane frames with semi-rigid beam-to-column and column-to-base plate connections are carried out first without considering concrete slab effects on floor beams in finite element analyses. The same optimization procedures are then repeated for the case of frames with composite beams. A program is coded in MATLAB for all optimization procedures. Results obtained from the examples show the applicability and robustness of the method. Moreover, it is proved that consideration of the contribution of concrete on the behavior of the floor beams enables a lighter and more economical design for steel frames with semi-rigid connections and column bases.

Modelling the performance of self-compacting SIFCON of cement slurries using genetic programming technique

  • Cevik, Abdulkadir;Sonebi, Mohammed
    • Computers and Concrete
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    • 제5권5호
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    • pp.475-490
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    • 2008
  • The paper explores the potential of applicability of Genetic programming approach (GP), adopted in this investigation, to model the combined effects of five independent variables to predict the mini-slump, the plate cohesion meter, the induced bleeding test, the J-fiber penetration value, and the compressive strength at 7 and 28 days of self-compacting slurry infiltrated fiber concrete (SIFCON). The variables investigated were the proportions of limestone powder (LSP) and sand, the dosage rates of superplasticiser (SP) and viscosity modifying agent (VMA), and water-to-binder ratio (W/B). Twenty eight mixtures were made with 10-50% LSP as replacement of cement, 0.02-0.06% VMA by mass of cement, 0.6-1.2% SP and 50-150% sand (% mass of binder) and 0.42-0.48 W/B. The proposed genetic models of the self-compacting SIFCON offer useful modelling approach regarding the mix optimisation in predicting the fluidity, the cohesion, the bleeding, the penetration, and the compressive strength.

Likelihood-Based Inference on Genetic Variance Component with a Hierarchical Poisson Generalized Linear Mixed Model

  • Lee, C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제13권8호
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    • pp.1035-1039
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    • 2000
  • This study developed a Poisson generalized linear mixed model and a procedure to estimate genetic parameters for count traits. The method derived from a frequentist perspective was based on hierarchical likelihood, and the maximum adjusted profile hierarchical likelihood was employed to estimate dispersion parameters of genetic random effects. Current approach is a generalization of Henderson's method to non-normal data, and was applied to simulated data. Underestimation was observed in the genetic variance component estimates for the data simulated with large heritability by using the Poisson generalized linear mixed model and the corresponding maximum adjusted profile hierarchical likelihood. However, the current method fitted the data generated with small heritability better than those generated with large heritability.