• Korean Journal of Microbiology
• /
• v.39 no.2
• /
• pp.114-117
• /
• 2003

In molecular biology, it is necessary to develop an easy and rapid method to identify a specific DNA sequence. Though Southern and Northern blot techniques have been used widely for the analysis of gene structure and function, those methods are inconvenient in the points that we need to control incubation temperature, time, and other parameters to get the final result. In this study, we report a new method for the rapid analysis of specific DNA sequence with the modification of an immunochromatographic method. The lateral flow DNA analysis strip is composed of a sample pad, a nitrocellulose membrane for the separation and propagation of analytes, and an absorption pad for the generation of capillary action. Capture DNA was immobilized on the membrane by UV cross-linking and target DNA was labeled with Cy-5 for signaling. The samples containing target DNA were applied onto the sample pad, incubated for 15 min for separation, and scanned with a GSI fluorescence scanner. Though the hybridization reaction occurs in a short time without any washing steps, there appears to be little cross hybridization between the different sequences. The result showed a possibility that the new method can be used for the rapid identification of specific DNA sequence among the samples.

• Korean Journal of Heritage: History & Science
• /
• v.40
• /
• pp.387-411
• /
• 2007

The analysis of ancient DNA (aDNA) has become increasingly considerable anthropological, archaeological, biological and public interest. Although this approach is complicated by the natural damage and exogenous contamination of a DNA, archaeologists and biologists have attempted to understand issues such as human evolutionary history, migration and social organization, funeral custom and disease, and even evolutionary phylogeny of extinct animals. Polymerase chain reaction(PCR) is powerful technique that analyzes DNA sequences from a little extract of an ancient specimen. However, deamination and fragmentation are common molecular damages of aDNA and cause enzymatic inhibition in PCR for DNA amplification. Besides, the deamination of a cytosine residue yielded an uracil residue in the ancient template, and results in the misincorporation of an adenine residue in PCR. This promotes a consistent substitution (cytosine thymine, guanine adenine) to original nucleotide sequences. Contamination with exogenous DNA is a major problem in aDNA analysis, and causes oversight as erroneous conclusion. This report represents serious problems that DNA modification and contamination are the main issues in result validation of aDNA analysis. Now, we introduce several criterions suggested to authenticate reliance of aDNA analysis by many researchers in this field.

• Fisheries and Aquatic Sciences
• /
• v.25 no.5
• /
• pp.264-275
• /
• 2022

A non-destructive environmental DNA protocol for the genetic analysis of sea cucumber (Apostichopus japonicus) resources DNA was established. Among the several commercial DNA extraction kits, the DNeasy^® Plant Mini Kit was selected as the best choice to obtain the high-quality genomic DNAs from the mucous sea cucumber. As the temperature and incubation time increased, the amount of extracted environmental DNA was also large, but it was judged that the increased amount did not affect as much as 2-3 times. Therefore, these conditions were not considered to be the main factors to consider in actual environmental DNA extraction. However, the amount of seawater relative to the size of the sample was judged as a major consideration, and a sufficient amount of environmental DNA for analysis was secured when stored within 1 min while stirring the volume of seawater corresponding to the total sea cucumber weight (g). In securing the environmental DNA of sea cucumbers, the mortality rate of sea cucumbers in all experiments was 0, and it was judged that the effects of sea cucumbers were not significant through this treatment. Through the results of this study, sea cucumber DNA research, which has been conducted in a destructive method, can be conducted non-destructively through environmental DNA analysis. Through this study, we have secured a standard protocol that can successfully extract the sea cucumber DNA through environmental DNA. It is not only excellent in terms of time and cost of traditional DNA analysis method currently used, but it is completely non-destructive in the ecosystem of the survey area. It is believed that the system can be transformed in a way that does not affect it. However, it is thought that various standard protocols should be established considering the characteristics of each type.

• Analytical Science and Technology
• /
• v.21 no.4
• /
• pp.338-343
• /
• 2008

Extraction of DNA from skeletal material is of great importance in the identification of human remains, but is particularly difficult because the high amount of microbial DNA was often co-extracted with human bone DNA. We found that a phenol/chloroform extraction, followed by ultrafiltration, and cleanup by via the $QIAquick^{(R)}$ PCR purification kit yields higher amounts of human genomic DNA compared with extraction by the column affinity $method^{(R)}$ alone. Ultrafiltration extraction of human DNA from ten exhumed bone samples yielded $0.041-1.120ng/{\mu}L$ DNA (mean = $0.498ng/{\mu}L$ DNA), and purification using the column affinity resulted in $0.016-0.064ng/{\mu}L$ DNA (mean = $0.034ng/{\mu}L$ DNA). Although the STR genotyping by the column affinity method was partially successful, all DNA samples by the ultrafiltration method produced full profiles from the multiplex PCR. The efficiency of STR genotyping was in accordance with the amounts of the human DNA extracted.

• Environmental Mutagens and Carcinogens
• /
• v.18 no.2
• /
• pp.83-88
• /
• 1998

To detect the mutation in a given sequence, there are variety of methods developed by use of the gel electrophoresis. One of the methods, TGGE (Temperature Gradient Gel Electrophoresis), is a popular technique because it can detect mutations in DNA fragment with ease and at low cost. This study used 200 bp BamHI-digested DNA fragment containing the human $\varepsilon$-globin promoter which was mutated[$\varepsilon$ F1*(-141), GATA- I*(-163), and GATA-1* & $\varepsilon$F1]. This BamHI-digested DNA fragment was directly used to detect the mutated DNA fragment on 50% denaturant gel with temperature gradient of 45$^{\circ}C$ through $53^{\circ}C$. In agreement with the theoretical result of MELTSCAN program (Brossette and Wallet, 1994) the mobilities of mutated DNA fragments were shown to be nearly distinguished on the temperature gradient gel. In contrast to the above result the heteroduplex analysis under the temperature gradient condition was shown to detect the mutated DNA fragments through the heteroduplex formation between strands of mutated DNA and wild-type DNA.

• Biomedical Science Letters
• /
• v.15 no.3
• /
• pp.229-232
• /
• 2009

DNA isolation for PCR-based short tandem repeat (STR) analysis is essential to recover high yields of amplifiable DNA from low copy number (LCN) DNA samples. There are different methods developed for DNA extraction from the small bloodstain and gloves, commonly found at crime scenes. In order to obtain STR profiles from LCN DNA samples, DNA extraction protocols, namely the automated $iPrep^{TM}$ $ChargeSwitch^{(R)}$ method, the automated $QIAcube^{TM}$ method, the automated $Maxwell^{(R)}$ 16 DNA $IQ^{TM}$ Resin method, and the manual $QIAamp^{(R)}$ DNA Micro Kit method, were evaluated. Extracted DNA was quantified by the $Quantifiler^{TM}$ Human DNA Quantification Kit and DNA profiled by $AmpFISTR^{(R)}$ $Identifiler^{(R)}$ Kit. Results were compared based on the amount of DNA obtained and the completeness of the STR profiles produced. The automated $iPrep^{TM}$ $ChargeSwitch^{(R)}$ and $QIAcube^{TM}$ methoas produced reproducible DNA of sufficient quantity and quality trom the dried blood spot. This two automated methods showed a quantity and quality comparable to those of the forensic manual standard protocols normally used in our laboratory. In our hands, the automated DNA extraction method is another obvious choice when the forensic case sample available is bloodstain. The findings of this study indicate that the manual simple modified $QIAamp^{(R)}$ DNA Micro Kit method is best method to recover high yields of amplifiable DNA from the numerous potential sources of LCN DNA samples.

• Korean Journal of Microbiology
• /
• v.37 no.1
• /
• pp.56-60
• /
• 2001

Molecular typing of Bacillus anthracis has been extremely difficult due to the lack of polymorphic DNA markers. Aiming to develop a DNA marker specific for Bacillus anthracis and to be able to discriminate this species from Bacillus genus, we applied the random amplified polymorphic DNA (RAPD)-PCR. We have identified B. anthracis from various Bacillus species. The analysis performed by RAPD clearly demonstrated substantial genetic variations among Bacillus species. This type of analysis is an easy, quick and highly discriminatory technique that may help in diagnosis of anthrax.

• Proceeding of EDISON Challenge
• /
• 2016.03a
• /
• pp.269-269
• /
• 2016

DNA origami is the most fitting nano-technology for synthesis of complex nano-structures. DNA crossover which ties DNA helices together are the main reason for the stable sustenance of origami structures with respect to other nano-scale structures. The mechanical properties of DNA crossovers have profound connection with structural rigidity, and it is a known fact that the rigidity changes depending on the arrangement of crossovers. It is possible to control the rigidity of origami structures for functionality and furthermore extends the field of DNA origami application. Here, we investigate the effect of crossovers on 2-Dimensional DNA structures varying crossover arrangement by sensitivity analysis based on finite element model. The crossover properties obtained from this analysis are compared with the existing experimental results.

• The Korean Journal of Cytopathology
• /
• v.6 no.1
• /
• pp.10-17
• /
• 1995

Anaplastic carcinoma of the thyroid gland is one of the most malignant tumors. Recently, DNA ploidy measured by flow cytometry and image analysis has been suggested as an additional useful indicator of tumor behavior. Studies on the occurrence and clinical significance of DNA aneuploidy in anaplastic carcinoma of the thyroid are rare. In this study, the pattern of DNA ploidy was measured by image analysis on Papanicolaou stained slides in four cases of anaplastic carcinoma and also measured by flow cytometry using paraffin blocks in two cases. In all cases of anaplastic carcinoma, DNA aneuploidy was found by image analaysis. By flow cytometry, one case had a diploid peak and the other case had an aneuploid peak. According to the above results, we conclude that anaplastic carcinoma of the thyroid glands have a high incidence of DNA aneuploidy and image analysis using Papanicolaou stained slides is a useful method in detecting DNA aneuploidy.

• Korean Journal of Ecology and Environment
• /
• v.54 no.3
• /
• pp.221-228
• /
• 2021

Recently, environmental DNA (eDNA)-based metabarcoding approaches have been proposed to evaluate the status of freshwater ecosystems owing to various advantages, including fast and easy sampling and minimal habitat disruption from sampling. Therefore, as a case study, we applied eDNA metabarcoding techniques to evaluate the effects of an abandoned mine land located near a headwater stream of Nakdonggang River, South Korea, by examining benthic macroinvertebrate diversity and compared the results with those obtained using the traditional Surber-net sampling method. The number of genera was higher in Surber-net sampling (29) than in the eDNA analysis (20). The genus richness tended to decrease from headwater to downstream in eDNA analysis, whereas richness tended to decrease at sites with acid-sulfated sediment areas using Surber-net sampling. Through cluster analysis and non-metric multidimensional scaling, the sampling sites were differentiated into two parts: acid-sulfated and other sites using Surber-net sampling, whereas they were grouped into the two lowest downstream and other sites using eDNA sampling. To evaluate freshwater ecosystems using eDNA analysis in practical applications, it is necessary to constantly upgrade the methodologies and compare the data with field survey methods.