• 한국식물병리학회지
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• 제12권4호
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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.

• 한국응용곤충학회지
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• 제36권1호
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• pp.96-104
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• 1997

DNA 다형성을 이용한 누에 유전자 해석기술을 개발하기 위하여 광식성 누에 계통 J111과 비광식성계통 $C_3$의 DNA를 분리하여 유전자 은행을 제작하였다. 누에 유전자 은행은 genomic DNA를 EcoRI로 절단한후 pUC18에 ligation 시켜 DH5$\alpha$ E. coli에 형질전환 시켰다. 형질전환 후 얻어진 colony는 15개 누에 품종의 genomic DNA에 hybridization하였을 때 누에의 품종에 관계없이 highly repetitive, moderately repetitive 및 single 혹은 low copy number 로 구분되었다. RFLP마커에 적합한 single 및 low-copy number band만을 형성하는 colony probe을 신속하게 선발하고자 colony또는 genomic DNA로 hybridization하였다. Single 및 low-copy number의 특성을 가진 219개의 clone을 선발하여 Hind III등 8종의 제한효소별로 처리한 genomic DNA를 이용하여 다형성을 검정하여 J111과 $C_3$ 계통간 다형성을 보인 46개의 clone을 선발하였다. 선발된 clone의 일부를 J111과 $C_3$를 교배하여 얻은 $F_2$의 blot에 hybridization 결과 RFLP clone들이 양친검정에 이용가능하여 누에 RFLP 연관 지도 작성의 기반을 조성하게 되었다.

• 한국균학회지
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• 제25권4호통권83호
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• pp.362-368
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• 1997

재조합 DNA probe를 이용하여 국내 Fusarium oxysporum 분화형간의 분류 가능성을 탐색하고 그들의 유전적 변이를 분석하였다. F. oxysporum f. sp. lycopersici, cucumerinum, fragariae, garlic, sesami 등 5종의 분화형을 공시하여 RFLP 분석을 실시하였다. Repetitive copy clone인 세종의 재조합 클론 pFC46, pFC52, pFC57을 이용하여 HindIII로 처리한 F. oxysporum의 genomic DNA에 대해 southern hybridization한 결과 나타난 밴드의 양상은 분화형에 따라 차이가 명확히 밝혀져 이들을 이용한 분류가 가능하였다. 또한 RFLP 분석 결과 f. sp. sesami는 다른 분화형에 비해 다소 변이가 심했으나 다른 분화형들은 변이가 거의 없어 f. sp. sesami를 제외한 f. sp. lycopersici 등 4종의 Fusarium oxysporum 분화형의 균주들은 채집 지역에 관계없이 대체로 유전적으로 안정되어 있는 것으로 판단되었다. Hybridization밴드의 양상에 기초하여 유전적 유연관계를 집괴 분석한 결과 각 분화형별로 유사도가 매우 높게 별도의 유사군을 형성하였다.

• 한국식물병리학회지
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• 제10권1호
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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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• 제39권1호
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• pp.49-55
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• 1996

본 연구는 마늘(Allium sativum L.)의 기초적인 유전적 특성을 파악하기 위해, 단양마늘을 대상으로 염색체 DNA의 반복서열의 양상을 확인하고, 고반복서열이 매우 빠르게 reassociation되는 특성을 이용하여 이들에 해당되는 부분을 분리하고, 클로닝하였다. 이들 고반복서열 클론의 게놈 내의 copy수는 대체적으로 $10^{5}~10^{7}$이었다. 이 중 일부 클론의 염기서열과 분석한 결과, G/C 함량은 25~40% 정도로 낮았고, 일부서열의 내부에서는 소단위의 염기서열이 반복배열되어 있었다. 단양을 비롯한 문경, 서산, 의성 품종 사이에서 해당 반복서열의 변이정도를 조사하기 위하여, 다섯종류의 고반복서열을 탐침으로 이들 품종 마늘에 대한 RELP(restriction fragment length polymorphism)분석을 한 결과 이들 서열의 유전적변이는 거의 나타나지 않았다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 춘계 학술대회지
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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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• 제4권4호
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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.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2001년도 제2회 생물정보 워크샵 (DNA Chip Bioinformatics)
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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