• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.113-116
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• 2001

Chromosomal variation was investigated in the female and male somaclones regenerated from the leaf segment culture of Rumex acetosa L. Difference in phenotype depending on the sexuality was not observed. In female somaclones, 21 among 25 somaclones carried the same chromosome complements (2n＝14) with wildtype and others were tetraploids (2n=28), Considerable chromosomal variation was found in male somaclones. Only 4 among 20 somaclones carried normal chromosome number (2n=15) and 13 somaclones were aneuploids.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.22-22
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• 2017

Genetic diversity is one of fundamental parameters for rice cultivar improvement. Rice mutants are also a new source for rice breeding innovation. In this study, ninety-three SSR markers were applied to evaluate the genetic variation among nineteen rice mutant lines. The results showed that a total of 169 alleles from 56 polymorphism markers was recorded with an average of 3.02 alleles per locus. The values of polymorphism information content (PIC) varied from 0.09 to 0.79. The maximum number of alleles was 7, whereas the minimum number of alleles was 2. The heterozygosity values ranged from 0.10 to 0.81. Four clusters were generated using the unweighted pair group method with arithmetic mean (UPGMA) clustering. Fourteen phenotype characteristics were also evaluated. The correlation coefficient values among these phenotye characteristics were obtained in this study. Genetic diversity information of rice mutant lines can support rice breeders in releasing new rice varieties with elite characterisitics.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.14-14
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• 2022

Greenhouse gas emissions are one of the critical factors that drive change in rice cropping systems. Within this changing system, less water irrigation and chemical fertilizer are seriously considered, as well combining precision farming technologies with irrigation control. Water and phosphorus (P) fertilizer are two of the most critical inputs in rice cultivation. Due to the lack of water availability in the system, P fertilizer is not available, especially in acidic soil conditions. Moreover, the various types of abiotic stresses, such as drought, high temperature, salinity, submergence, and limited fertilizer result in significant yield loss in the system. Even in the late stage of growth, the waves caused by diseases and insects make the field more unfruitful. Therefore, agronomists and breeders need to identify the secondary phenotypes to estimate the yield loss of when stress appears. The prediction will be clearer if we have a set of markers tagging the causal variation and the associated precise phenotype indices. Although there have been various studies for abiotic stress tolerance, we still lack functional molecular markers and phenotype indices. This is due to the underlying challenges caused by environmental factors in highly unpredictable regional and yearly environmental conditions in the field system. Pupl (phosphorus uptake 1) is still known as the first QTL associated with phosphorus uptake and have been validated in different field crops. Interestingly, some pyramiding lines of Pupl and other QTLs for other stress tolerances showed preferable phenotypes in the yield. Precise physiological studies with the help of genomics are on-going and some results will be discussed.

• Toxicological Research
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• v.17
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• pp.145-155
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• 2001

Cytochrome P4502C19 (CYP2C19) is one of human polymorphic xenobiotic-metabolizing enzymes. The enzyme has been reported to catalyze more than 70 substrates, involving more than 100 reactions. These include several classes of therapeutic agents (e.g. anti-microbial. cardiovascular, psycho-active, etc.), sex hormones and insecticides. Associations of the CYP2C19 genotype/phenotype with individual differences in drug efficacy (e.g. diazepam, omeprazole, proguanil) and toxicity (e.g. mephenytoin, barbiturates) have been documented by many investigators. At least 11 allelic variants of CYP2C19 gene were reported to date. Most of the mutant alleles found in the poor metabolizer (PM) led to the production of truncated and/or inactive proteins. Except for the exon 6, single-nucleotide mutations were reported in all nine exons of the gene. Genetic polymorphism of CYP2C19 shows marked interethnic variation with the population frequencies of PM phenotype ranging from 1∼2% up to more than 50%. The prevalence of CYP2C19 PM tends to be higher in Asian and certain Pacific Islanders than other race or ethnic specificity. Genotyping results of CYP2C19 also revealed that there are different proportions of individual mutant alleles among ethnic populations. This may, in part, explains the interethnic difference in the metabolism of certain drugs (i.e. diazepam), though they were from the same CYP2C19 phenotype. Recently, our research group has studied the genotype and phenotype of CYP2C19 and found that the PM frequency (7∼8%) in Thais is lower than other Asian populations. Molecular and clinical impacts of this finding warrant to further investigation.

• Molecules and Cells
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• v.24 no.2
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• pp.255-260
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• 2007

Bone marrow (BM) derived mesenchymal stem cells (MSC) are pluripotent cells which can differentiate into osteogenic, adipogenic and other lineages. In spite of the broad interest, the information about the changes in BM cell composition, in particularly about the variation of MSC number and their properties in relation to the age of the donor is still controversial. The aim of this study was to investigate the age associated changes in variations of BM cell composition, phenotype and differentiation capacities of MSC using a rat model. Cell populations were characterized by flow cytometry using light scattering parameters, DNA content and a set of monoclonal antibodies. Single cell analysis was performed by conventional fluorescent microscopy. In vitro culture of MSC was established and their phenotype and capability for in vitro differentiation into osteogenic and adipogenic cells was shown. Age related changes in tibiae and femurs, amount of BM tissue, BM cell composition, proportions of separated MSC and yield of MSC in 2 weeks of in vitro culture were found. At the same time, neither change in phenotype no in differentiation capacities of MSC was registered. Age-related changes of the number of MSC should be taken into account whenever MSC are intended to be used for investigations.

• Journal of Preventive Medicine and Public Health
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• v.27 no.3 s.47
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• pp.569-579
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• 1994

The genetically determined ability to metabolize debrisoquine (DBR) is related to risk of lung cancer and DBR hydroxylation exhibits wide inter-individual variation. In this study, 100 korean adults were tested for their ability to metabolize DBR. The DBR metabolic phenotype were determined by metabolic ratio (MR, DBR / 4-HDBR) which is the percent dose excreted as unchanged DBR divided by the percent dose excreted as 4-hydroxyebrisoquine(4-HDBR) in a aliquot of an eight hour urine sample, after 10mg DBR test dose administration. Analysis was performed on a capillary gas chromatograph fitted with electron capture detector. The results were as follows; 1 Geometric mean of DBR MR was 0.32 in male,0.27 in female,0.30 in total and the distribution of log (MR) was seemed to follow normal distribution. 2. Metabolic ratio of DBR was higher in non-smoker and non-drinker than in smoker and drinker without any statistically significant difference. 3. None of personal factors was significantly related to DBR MR except age. 4. The DBR metabolic phenotype was extensive metabolizer(EM) 93, intermediate metabolizer(IM) 7 by traditional method and EM 98, IM 3 by Caporaso's method. The poor metabolizer (PM) phenotype was not found by either method. 5. Maximal expected PM phenotype was 0.36% by traditional method and 0.04% by Caporaso's method.

• Korean Journal of Veterinary Research
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• v.41 no.4
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• pp.543-548
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• 2001

To examine the fate of the injected peritoneal mast cells (PMCs), we injected PMCs (500 or $10^5$) derived from WBB6F1-green fluorescent protein(GFP) mice into stomach wall of $WBB6F1-W/W^v$ mice. When 500 PMCs were injected, the proportion of alcian blue $(AB)^+$ mast cells to $GFP^+$ mast cells in the muscle was 25.0% on day 1, but decreased to 0.9% on day 7. Then, it increased to 98.2% on day 35. In contrast,$GFP^+$ mast cells in the mucosa were not detectable on day 1, 3, and 7 after injection. On day 35, the proportion of $AB^+$ mast cells to $GFP^+$ mast cells in the mucosa was 97.0%. When $10^5$ PMCs were injected, the proportion of $AB^+$ mast cells to $GFP^+$ mast cells in the muscle was more than 88.2%, and that in the mucosa was more than 86.3% from day 1 through 35 after injection. These results indicated that percentage of degranulation on day 1, 3, 7, 14 after injection of 500 PMCs was significantly higher than that after injection of $10^5$ PMCs. Futhermore, when 500 PMCs were injected, protease expression phenotypes of PMCs changed from day 14 after injection. When $10^5$ PMCs were injected, protease expression phenotype of PMCs did not change after injection. Such degranulated PMCs may acquire the new phenotype and adapt the new tissue.

• Korean Journal of Plant Tissue Culture
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• v.24 no.3
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• pp.175-181
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• 1997

Plants were regenerated from hypocotyl protoplast culture of cabbage (F$_1$hybrid Green Challenger) and were transplanted on fields. The ploidy level of regenerated and seed-grown plants was measured by flow cytometry. In total 125 regenerated plant, diploid (2n), tetraploid(4n), and mixoploid (2n+4n) were 72.8%, 25.6%, and 1.6%, respectively. Most of the regenerated plants had normal phenotype, whereas several plane showed abnormal phenotype such as heavy leaf incision, savoy, and wave. The regenerated plants with abnormal phenotype and different ploidy level were analysed by isozyme and RAPD, but no significant difference was found.

• Korean Journal of Medicinal Crop Science
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• v.10 no.4
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• pp.263-268
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• 2002

Acifluorfen-tolerant callus lines of Solanum ptycanthum were isolated by stepwise selection. Growth of the unselected line was completely inhibited at 0.5 uM. while some selected lines grew at 8 uM acifluorfen. Twenty-two of twenty-five acifluorfen-tolerant callus lines regenerated shoots. Many of the regenerated somaclones were variants, differing in leaf shape, leaf color, number of flower parts, flower color, and fertility. The acifluorfen tolerant S. ptycanthum callus lines differed.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.1
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• pp.1-14
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• 2021

Cardiovascular disease (CVD) accounts for approximately 30% of all deaths worldwide and its prevalence is constantly increasing despite advancements in medical treatments. Cardiac remodeling and dysfunction are independent risk factors for CVD. Recent studies have demonstrated that cardiac structure and function are genetically influenced, suggesting that understanding the genetic basis for cardiac structure and function could provide new insights into developing novel therapeutic targets for CVD. Regular exercise has long been considered a robust nontherapeutic method of treating or preventing CVD. However, recent studies also indicate that there is inter-individual variation in response to exercise. Nevertheless, the genetic basis for cardiac structure and function as well as their responses to exercise training have yet to be fully elucidated. Therefore, this review summarizes accumulated evidence supporting the genetic contribution to these traits, including findings from population-based studies and unbiased large genomic-scale studies in humans.