• Journal of Microbiology and Biotechnology
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• v.4 no.3
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• pp.171-175
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• 1994

To find new crystal protein genes, we screened 42 Bacillus thuringiensis strains of serovar standards by Southern hybridization with a cryI-specific probe which was amplified from B. thuringiensis subsp. kurstaki HDl by polymerase chain reaction (PCR). Two strains, B. thuringiensis subsp. entomocidus HD9 and subsp. subtoxicus HD109, generated weak signals under the low-stringency hybridization conditions. Further analysis with Southern hybridization revealed that the two strains contained cryIB genes which are slightly different from those of B. thuringiensis subsp. thuringiensis HD2. These results were confirmed by PCR with cryIB-specific primers followed by the restriction analysis of PCR products.

• Communications for Statistical Applications and Methods
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• v.13 no.1
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• pp.167-175
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• 2006

It has long been recognized that cancer is a genetic disease. To find this measures of genetic instability, stain cells with chromosome specific probes using chromosome in-situ hybridization technique is adopted. Even though in-situ hybridization technique is powerful, truncation of nuclei often results in under-representation of chromosome copies in slides due to the sectioning of tissue blocks. Because of this problem we suggest three different methods to analyze the cervical cancer data set. We observe that genetic instability is an increasing function of histology and our suggested model is the best in detecting genetic instability of tumorigenesis processes.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.376-379
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• 2003

DNA computing based DNA sequence Is operated through the biology experiment. Biology experiment used as operator causes illegal reactions through shifted hybridization, mismatched hybridization, undesired hybridization of the DNA sequence. So, it is essential to design DNA sequence to minimize the potential errors. This paper proposes method of the DNA sequence generation based evolutionary operation processor. Genetic algorithm was used for evolutionary operation and extra hardware, namely genetic algorithm processor was implemented for solving repeated evolutionary process that causes much computation time. To show efficiency of the Proposed processor, excellent result is confirmed by comparing between fitness of the DNA sequence formed randomly and DNA sequence formed by genetic algorithm processor. Proposed genetic algorithm processor can reduce the time and expense for preparing DNA sequence that is essential in DNA computing. Also it can apply design of the oligomer for development of the DNA chip or oligo chip.

• The Korean Journal of Zoology
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• v.30 no.4
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• pp.417-431
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• 1987

Isozyme analysis, morphometric comparison, and artificial hybridization test wereperformed to elucidate the patterns of genic variation, morphological differentiation, genetic incompatibility, and a probable path in speciation between two MDH allelotypes (MM type and MS type) of the Dark Chub Zacco temmincki, a fresh water fish inhabiting in Korean waters. The degree of genic variation of MS type(HD=.023, HG=.021) was twofold higher than that of MM type (HD=.013, HG=.014) but both allelotypes were far less than the average genic variation of fresh water Bish in general. The average genetic similarities among 7 populations of MM type and 6 Populations of MS type were S=.947 and S=.966 respectively, whereas the value between two allelotypes was S=.853. Presumed divergent time of two allelotypes was estimated to be about 700 thousand years ago. Discriminant function analysis based on 18 morphometric characters of 302 specimens representing 12 populations revealed no morphological difference between two allelotypes. Artificial hybridization test indicates that there is an obvious genetic incogpatibility between two allelotypes and therefore it is assumed that isolating mechanism is completed.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.726-732
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• 1996

To improve the fermentation characteristics(such as starch-degradability, ethanol tolerance, sugar and high-temperature tolerance) of recombinant haploid yeast Saccharomyces diastaticus K114, hybridization technique was used. The hybridization partner was S. diastaticus 1177 which had good glucoamylase activity and fermentabi- lity. The best hybrid HH64 showed improved ethanol tolerance, sugar and high-temperature tolerance. Especia- lly, the starch-fermentability was significantly improved, since the hybrid produced 1.60% (w/v) ethanol from 4% (w/v) starch, while the recombinant haploid K114 produced 1.30% (w/v) ethanol. The optimum temperature and pH for the starch-fermentation by the hybrid HH64 was 30$\circ$C and 5, respectively. The hybrid yeast HH64 produced 7.5% (w/v) ethanol directly from 20% (w/v) starch.

• BMB Reports
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• v.34 no.1
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• pp.59-65
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• 2001

In subtractive hybridization, target sequences in the tester are enriched by hybridizing with an excess amount of driver, followed by removing the tester hybridized with the driver. All of existing subtractive cloning methods are designed to remove the tester/driver hybrid. The removal of hybrid, however, is often unsatisfactory For various reasons. In this study we developed a subtractive enrichment protocol in which the tester/driver can be completely removed by selecting only the tester/tester after hybridization. In this protocol both the tester and driver DNAs are ligated with same linker DNAs and amplified by polymerase chain reaction (PCR). The tester DNA is then digested with two different enzymes and used in subsequent hybridization with an excess driver. After hybridization, the DNA is ligated with the adaptor that is only compatible with the tester/tester. Since only the tester/tester can have the new adaptor, no tester/driver can be amplified by PCR in this protocol. Unlike other methods, a 100% subtraction efficiency can be achieved even though the enzymatic treatments used in the enrichment procedure are incomplete. Furthermore, only the hybridized tester DNA can have the new adaptor and be amplified by PCR, resulting in 100% denaturation in effect. The efficacy of this novel method was verified with the model system in which a known amount of the target sequence is included.

• International Journal of Industrial Entomology and Biomaterials
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• v.18 no.1
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• pp.41-48
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• 2009

The large bumblebee, Bombus terrestris, indigenous to Europe and used extensively for high-value crop pollination, has been artificially introduced in several parts of the world. Here we show the interspecific hybridization between bumblebee species, B. terrestris and B. ignitus, under laboratory conditions. The mating and oviposition percentages of the interspecific hybridization of a B. terrestris queen with a B. ignitus male were higher than those of the intraspecific mating of B. ignitus. Furthermore, the competitive copulation experiment indicated that the mating of B. ignitus males with B. terrestris queens was 1.8-fold more frequent than with B. ignitus queens. The interspecific hybridization of a B. ignitus queen with a B. terrestris male produced either B. ignitus workers or the B. ignitus male phenotype, and the hybridization of a B. terrestris queen with a B. ignitus male produced B. terrestris males. Genetic tests using a portion of the mitochondrial COI gene for the parent and hybrid phenotypes indicated that mitochondrial DNA in the interspecific hybridization was maternally inherited. Our results indicated that interspecific hybridization occurred between B. ignitus and B. terrestris, which suggests that the hybridization will have a negative impact of competition and genetic pollution of native bumblebees.

• BMB Reports
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• v.37 no.4
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• pp.439-444
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• 2004

Double stranded targets on the cDNA microarray contain representatives of both the coding and noncoding strands, which will introduce hybridization competition with probes. Here, the effect of double and single strands of targets on the signal intensity and the ratios of Cy5/Cy3 within the same slide were compared. The results show that single stranded targets can increase the hybridization efficiency without changing the Cy5/Cy3 ratio. Based on these results, a new strategy was established by generating cDNA targets with asymmetric PCR, instead of conventional PCR, to increase the sensitivity of the cDNA microarray. Furthermore, the feasibility of this approach was validated. The results indicate that the cDNA microarray system based on asymmetric PCR is more sensitive, with no decrease in the reliability and reproducibility as compared with that based on conventional symmetric PCR.

• Journal of Genetic Medicine
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• v.12 no.1
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• pp.6-11
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• 2015

Intellectual disability (ID) is the most common disability among people under the age of 20 years. In the absence of obvious non-genetic causes of ID, the majority of cases of severe ID are thought to have a genetic cause. The advent of technologies such as array comparative genomic hybridization, single nucleotide polymorphism genotyping arrays, and massively parallel sequencing has shown that de novo copy number variations and single nucleotide variations affecting coding regions are major causes of severe ID. This article reviews the genetic causes of ID along with diagnostic approaches for this disability.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 1998.07a
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• pp.12-18
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• 1998

Tremendous progress has been made over the past quarter-century studying the genetics of gametogenesis and the resulting gametes and embryos. Studies merging molecular techniques and conventional cytogenetics are now beginning to bridge the gap between what we have learned about the meiotic process in males and females and what we know of the mitotic chromosomes of zygotes. Numerical abnormalities in sperm, oocytes and embryo can now diagnosed by fluorescence in situ hybridization (FISH). "At risk" couples can, therefore, have only unaffected embryos replaced in the sterus and avoid the possibility of terminating a pregnancy that might only be diagnosed as affected later gestation. Single-cell genetic analysis has also provided powerful tools for studying genetic defects arising during early human development. Recent studies of sperms, oocytes and cleavage-stage human embryos have revealed an unexpectedly high incidence. These genetic abnormalities are likely to contribute to early pregnancy loss and have important implications for improving pregnancy rates in infertile couples by assisted reproduction. The widespread use of preimplantation genetic diagnosis (PGD) awaits further documentatio of safety and accuracy. Other issues also must be addressed. First, the ethical issues regarding germ cell and embryo screening must be addressed including what diseases are serious enough to warrant the procedure. Another concern is the use of this technology for non-genetic disorders such as gender selection. Finally, the experimental nature of these procedure must continually be discussed with patients, and long-term follow-up studies must be undertaken. Development of more accurate and less expensive assays coupled with improved assisted reproductive technology success rates may make PGD a more widely use clinical tool. The future awaits these development.velopment.