• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.389-394
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• 1996

도열병균, Magnaporthe grisea, 균주간의 유전적 유연관계를 분석하고 그들의 유전에 관한 '기본 정보를 얻고자 DNA polymorphism 분석을 실시하였다. 기주가 다른 도열병 균주들이 공시되었고 cloning에 의해 벼 도열병균 KJ201레이스 균주로부터 생성된 임의 선발 genomic clone들이 공시균주들간의 polymorphism을 밝히기 위해 사용되었던 바 그중 repectitive sequence를 보유한 repeated copy clone 하나가 선발되었다. Clone pMJ6에 의해 밝혀진 repetitive sequence는 Southern hybridization시 벼 분리균주에는 약 30개, 다른 기주 분리균에도 20∼33개의 밴드를 형성하였다. 반면 피 분리균주에는 단지 두 개의 밴드만을 나타내 분리기주가 다른 균주간에 뚜렷한 polymorphism이 존재하였으며 parsimony 분석에서도 역시 아주 먼 cluster를 형성하여 피 분리균은 다른 기주 분리균과 유전적으로 상당히 먼 것으로 추정되었다. 공시균의 genomic DNA를 HindIII로 처리했을 때 pMJ6에 의한 밴드양상은 공시균을 EcoRI으로 처리했을 때의 MGR probe의 밴드 양상과 유사하여 이 repeated copy clone이 도열병균주간의 유전적 유연관계를 분석하는데 MGR 못지않게 유용할 것으로 보인다.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.96-104
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• 1997

A silkworm Bombyx mori genomic DNA library was constructed from polyphagous J111 strain and unpolyphagous $C_3$ strain to develop the genomic study by DNA makers. Genomic DNAs of two strains were digested with restriction enzyme EcoRI and ligated into pUC18. The ligated plasmids were transferred into E. coli host strain DH5$\alpha$. When the genomic DNAs were hybridized with insert DNAs from transformant, could be categorized from hybridization patterns to three groups as high repetitive sequence, moderately repetitive sequence, and low-copy number sequences. A total of 219 clones containing single or low-copy number sequence inserts were examined for any polymorphisms between two strains of J111 and $C_3$. Forty six clones showed RFLPs and 10 of these clones were used as a probe of analysis of $F_2$ population derived from crossing between J111 and $C_3$ strain. The genetic inheritance tested with each clones will be important tools to construct the genetic map of the silkworm, Bombyx mori.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.362-368
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• 1997

Five formae speciales of Fusarium oxysporum in Korea were examined using RFLP analysis to find the possibility for classification and analyze genetic variations. DNAs from F. oxysporum f. sp. lycopersici, cucumerinum, fragariae, garlic and sesami were used with three recombinant probes such as pFC46, pFC52 and pFC57. Distinct differences among five formae speciales of this fungus were detected in RFLP band patterns based on southern hybridization of genomic DNA using each recombinant clone, which was a repetitive copy probe. Strains belong to four formae speciales could be very stable in genetic variation except f. sp. sesami which has more variation than the others based on the RFLP analysis. They formed their own cluster which has high similarity within the same formae specialis resulted from the UPGMA analysis for genetic relationship analysis and each cluster represented its own formae specialis. The method using three recombinant DNA probes could be a good tool for classification of formae speciales in F. oxysporum.

• Korean Journal Plant Pathology
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• v.10 no.1
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• pp.1-6
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• 1994

Randomly chosen recombinant clones of Fusarium oxysporum were analysed to select useful probes for relatedness analysis of Fusarium oxysporum. Genomic DNA of F. oxysproum f. sp. cubense, digested with HindIII, was ligated to pUC118 and used to transform Escherichia coli strai DH5$\alpha$. Three clones were identified that hybridized to mutiple restriction fragments of some formae speciales of F. oxysporum. These probes detected repetitive sequences in HindIII or EcoRI digested DNAs. Repeated copy clone pFC46, pFC52 and pFC54 showed evident polymorphisms among ten formae speciales of this fungus. Since clone pFC 52 strongly hybridized to multiple EcoRI-digested restriction fragments of f. sp. cubense, it may be useful as a probe for analysis of other genetic characteristics of this forma specialis. The results suggest that our clones might be very useful as probes for relatedness analysis between or within formae speciales of Fusarium oxysporum.

• Journal of Plant Biology
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• v.39 no.1
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• pp.49-55
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• 1996

We have studied the DNA of Allium sativum L. with respect to highly repetitive sequences. Fast reassociated DNA fragments expected to be highly repetitive sequences based on $C_{o}t$ curve were isolated and characterized. Their copy numbers were approximately $10^{5}~10^{7}$ per haploid genome. Nucleotide sequences analysis of six candidates reveals that their G/C content were low, 25-40% and typical patterns of repeating sequences exist. Repeat sequences were used as probes to access restriction fragment length polymorphism (RFLP) of genomic DNAs of four local clones, Tanyang, Mungyong, So san, and Uisong. The hybridization pattern were very similar among these four local clones.clones.

• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.162-163
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• 1999

The goal of this research was (1) to describe the conditions and parameters required for the cell cycle synchronization and the accumulation of large number of metaphase cells in maize and other cereal root tips, (2) to isolate intact metaphase chromosomes from root tips suitable for characterization by flow cytometry, and (3) to construct chromosome-specific libraries from maize. Plant metaphase chromosomes have been successfully synchronized and isolated from many cereal root-tips. DNA synthesis inhibitor (hydroxyurea) was used to synchronize cell cycle, follwed by treatement with trifluralin to accumulate metaphase chromosomes. Maize flow karyotypes show substantial variation among inbred lines. thish variation should be sueful in isolating individual chromosome types. In addition, flow cytometry is a useful method to measure DNA content of individual chromosomes in a genotyps, and to detect chromosomal variations. Individual chromosome peaks have been sorted from the maize hybrid B73/Mol7. Libraries were generated form the DOP-PCR amplification product from each peak. To date, we have analyzed clones from a library constructed from the maize chromosome 1 peak. Hybridization of labeled genomic DNA to clone inserts indicated that $24\%,\;18\%,\;and\;58\%$ of the clones were highly repetitive, medium repetitive, and low copy, respectively. Fifty percent of putative low cpoy clones showed single bands on inbred screening, blots, and the remaining $50\%$ were low copy repeats. Single copy clones showing polymorphism will be mapped using recombinant inbred mapping populations. Repetitive clones are being characterized by Southern blot analysis, and will be screened by in situ hybridization for their potential utility as chromosome specific markers.

• Journal of Multimedia Information System
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• v.4 no.4
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• pp.255-262
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• 2017

In recent software development, repetitive code fragments (i.e., clones) are common due to the copy-and-paste programming practice, the framework-based development, or the reuse of same design patterns. Such similar code fragments are likely to introduce more bugs but are easily disregarded by a code reviewer or a programmer. In this paper, we present a code review tool to help code reviewers identify important code changes written by other programmers and recommend which changes need to be reviewed first. Specifically, to identify important code changes, our approach detects code clones across revisions and investigates them. Then, to help a code reviewer, our approach ranks the identified changes in accordance with several software quality metrics and statistics on those clones and changes. Furthermore, our approach allows the code reviewer to express their preferences during code review time. As a result, the code reviewer who has little knowledge of a code base can reduce his or her effort by reviewing the most significant changes that require an instant attention. To evaluate our approach, we integrated our approach with a modern IDE (e.g., Eclipse) as a plugin and then analyzed two third-party open source projects. The experimental results indicate that our approach can improve code reviewer's productivity.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2001.10a
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• pp.61-86
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• 2001

All cancers are caused by abnormalities in DNA sequence. Throughout life, the DNA in human cells is exposed to mutagens and suffers mistakes in replication, resulting in progressive, subtle changes in the DNA sequence in each cell. Since the development of conventional and molecular cytogenetic methods to the analysis of chromosomal aberrations in cancers, more than 1,800 recurring chromosomal breakpoints have been identified. These breakpoints and regions of nonrandom copy number changes typically point to the location of genes involved in cancer initiation and progression. With the introduction of molecular cytogenetic methodologies based on fluorescence in situ hybridization (FISH), namely, comparative genomic hybridization (CGH) and multicolor FISH (m-FISH) in carcinomas become susceptible to analysis. Conventional CGH has been widely applied for the detection of genomic imbalances in tumor cells, and used normal metaphase chromosomes as targets for the mapping of copy number changes. However, this limits the mapping of such imbalances to the resolution limit of metaphase chromosomes (usually 10 to 20 Mb). Efforts to increase this resolution have led to the "new"concept of genomic DNA chip (1 to 2 Mb), whereby the chromosomal target is replaced with cloned DNA immobilized on such as glass slides. The resulting resolution then depends on the size of the immobilized DNA fragments. We have completed the first draft of its Korean Genome Project. The project proceeded by end sequencing inserts from a library of 96,768 bacterial artificial chromosomes (BACs) containing genomic DNA fragments from Korean ethnicity. The sequenced BAC ends were then compared to the Human Genome Project′s publicly available sequence database and aligned according to known cancer gene sequences. These BAC clones were biotinylated by nick translation, hybridized to cytogenetic preparations of metaphase cells, and detected with fluorescein-conjugated avidin. Only locations of unique or low-copy Portions of the clone are identified, because high-copy interspersed repetitive sequences in the probe were suppressed by the addition of unlabelled Cotl DNA. Banding patterns were produced using DAPI. By this means, every BAC fragment has been matched to its appropriate chromosomal location. We have placed 86 (156 BAC clones) cytogenetically defined landmarks to help with the characterization of known cancer genes. Microarray techniques would be applied in CGH by replacement of metaphase chromosome to arrayed BAC confirming in oncogene and tumor suppressor gene: and an array BAC clones from the collection is used to perform a genome-wide scan for segmental aneuploidy by array-CGH. Therefore, the genomic DNA chip (arrayed BAC) will be undoubtedly provide accurate diagnosis of deletions, duplication, insertions and rearrangements of genomic material related to various human phenotypes, including neoplasias. And our tumor markers based on genetic abnormalities of cancer would be identified and contribute to the screening of the stage of cancers and/or hereditary diseases