• Biomedical Science Letters
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• v.28 no.3
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• pp.157-169
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• 2022

DNA typing is the typical technology in the forensic science and plays a significant role in the personal identification of victims and suspects. Short tandem repeat (STR) is the short tandemly repeated DNA sequence consisting of 2~7 bp DNA units in specific loci. It is disseminated across the human genome and represents polymorphism among individuals. Because polymorphism is a key feature of the application of DNA typing STR analysis, STR analysis becomes the standard technology in forensics. Therefore, the DNA database (DNA-DB) was first introduced with 4 essential STR markers for the application of forensic science; however, the number of STR markers was expanded from 4 to 13 and 13 to 20 later to counteract the continuously increased DNA profile and other needed situations. After applying expanded STR markers to the South Korean DNA-DB system, it positively affected to low copy number analysis that had a high possibility of partial DNA profiles, and especially contributed to the theft cases due to the high portion of touch DNA evidence in the theft case. Furthermore, STR marker expansion not only contributed to the resolution of cold cases but also increased kinship index indicating the potential for improved kinship test accuracy using extended STR markers. Collectively, the expansion of the STR locus was considered to be necessary to keep pace with the continuously increasing DNA profile, and to improve the data integrity of the DNA-DB.

• Journal of Nutrition and Health
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• v.48 no.5
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• pp.390-397
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• 2015

Purpose: In this study, we investigated the effects of chronic alcohol and excessive iron intake on mitochondrial DNA (mtDNA) damage and the progression of alcoholic liver injury in rats. Methods: Twenty-four Sprague-Dawley male rats were divided into four groups (Control, EtOH, Fe, and EtOH + Fe), and fed either control or ethanol (36% of total calories) liquid diet with or without 0.6% carbonyl iron for eight weeks. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, liver malondialdehyde concentrations were measured by colorimetric assays. Liver histopathology was examined by Hematoxylin-eosin staining of the fixed liver tissues. The integrity of the hepatic mtDNA and nuclear DNA was measured by long-range PCR. The gene expression levels of cytochrome c oxidase subunit 1 (Cox1) and NADH dehydrogenase subunit 4 (Nd4) were examined by real-time PCR. Results: Serum ALT and AST activities were significantly higher in the EtOH+Fe group, as compared to the Control group. Similarly, among four groups, liver histology showed the most severe lipid accumulation, inflammation, and necrosis in the EtOH + Fe group. PCR amplification of near-full-length (15.9 kb) mtDNA showed more than 50% loss of full-length product in the liver of the EtOH + Fe group, whereas amounts of PCR products of a nuclear DNA were unaffected. In addition, the changes in the mtDNA integrity showed correlation with reductions in the mRNA levels of mitochondrial gene Cox1 and Nd4. Conclusion: Our data suggested that the liver injury associated with excessive iron and alcohol intake involved mtDNA damage and corresponding mitochondrial dysfunction.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2989-2993
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• 2016

The commonest cancer in Egyptian females occurs in the breast cfDNA is a non-invasive marker for tumor detetion and prognostic assessment in many types of cancer including breast cancer. This study aimed to assess the role of cfDNA and its fragmentation pattern in breast cancer prognosis and treatment response. Forty female patients with malignant breast tumors and a comparable group of healthy blood donors were enrolled prospectively. cfDNA levels and fragmentation patterns were investigated after cfDNA extraction, gel electrophoresis and gel analysis. The percentage of breast cancer patients positive for cfDNA (92.5%) was significantly higher than that of controls (55%). Also, mean concentration of cfDNA was significantly higher than in the control group (P<0.05). Most Her-2 positive patients had long cfDNA fragments, this being significant as compared to Her-2 negative patients (P<0.05). Metastasis was also positively linked to significantly higher cfDNA (P<0.05) and the mean cfDNA integrity index was significantly higher in non-responders compared to treatment responders (P<0.05). In conclusion, both qualitative and quantitative aspects of cfDNA and its different fragments in breast cancer patients could be related to prognosis, metastasis and treatment response. Long cfDNA fragments could be particularly useful for prediction purposes.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.05a
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• pp.132.1-132.1
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• 2003

• 대한생식의학회:학술대회논문집
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• 2007.11a
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• pp.102.2-103
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• 2007

• Clinical and Experimental Reproductive Medicine
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• v.51 no.1
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• pp.13-19
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• 2024

Radiofrequency electromagnetic radiation (RF-EMR) from various sources may impact health due to the generation of frequency bands. Broad pulses emitted within frequency bands can be absorbed by cells, influencing their function. Numerous laboratory studies have demonstrated that mobile phones-generally the most widely used devices-can have harmful effects on sex cells, such as sperm and oocytes, by producing RF-EMR. Moreover, some research has indicated that RF-EMR generated by mobile phones can influence sperm parameters, including motility, morphology, viability, and (most critically) DNA structure. Consequently, RF-EMR can disrupt both sperm function and fertilization. However, other studies have reported that exposure of spermatozoa to RF-EMR does not affect the functional parameters or genetic structure of sperm. These conflicting results likely stem from differences among studies in the duration and exposure distance, as well as the species of animal used. This report was undertaken to review the existing research discussing the effects of RF-EMR on the DNA integrity of mammalian spermatozoa.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.1
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• pp.24-30
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• 2012

In this study, we have examined the effects of the storage time and temperature on DNA quality and have also studied the effects of the hydration buffer in which DNA is dissolved. This study was performed using 160 human blood samples collected with informed consent from 2007 to 2008 in the hospital where this cohort study was performed. The DNA extracted was dissolved using distilled water (DW) or Tris-EDTA (TE) buffer, and stored in the deep freezer or refrigerator for up to 10 weeks at $-70^{\circ}C$, $-20^{\circ}C$, $4^{\circ}C$, and $25^{\circ}C$, respectively. DNA integrity was determined by the degree of smearing of DNA on the gel. After four weeks, all of the 20 DNA samples dissolved in DW and stored at $25^{\circ}C$ were entirely degraded. After 10 weeks, 6 of the 20 DNA samples dissolved in TE buffer and stored at $25^{\circ}C$ were fairly degraded, and 4 of the 20 DNA samples dissolved in DW and stored at $4^{\circ}C$ were fairly degraded. The 20 DNA samples dissolved in TE buffer and stored at $4^{\circ}C$ were stable for 10 weeks. DNA samples stored at $-20^{\circ}C$ and $-70^{\circ}C$ did not appear to degrade in either DW or TE buffer, even at the 10-week point. We suggest that TE buffer should use for DNA elution, in order to protect against degradation and to preserve DNA for a long period of time, and the samples should be stored at $-20^{\circ}C$ or $-70^{\circ}C$.

• Journal of Genetic Medicine
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• v.13 no.1
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• pp.1-13
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• 2016

Although some mutations are beneficial and are the driving force behind evolution, it is important to maintain DNA integrity and stability because it contains genetic information. However, in the oxygen-rich environment we live in, the DNA molecule is under constant threat from endogenous or exogenous insults. DNA damage could trigger the DNA damage response (DDR), which involves DNA repair, the regulation of cell cycle checkpoints, and the induction of programmed cell death or senescence. Dysregulation of these physiological responses to DNA damage causes developmental defects, neurological defects, premature aging, infertility, immune system defects, and tumors in humans. Some human syndromes are characterized by unique neurological phenotypes including microcephaly, mental retardation, ataxia, neurodegeneration, and neuropathy, suggesting a direct link between genomic instability resulting from defective DDR and neuropathology. In this review, rare human genetic disorders related to abnormal DDR and damage repair with neural defects will be discussed.

• Environmental Engineering Research
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• v.11 no.5
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• pp.277-284
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• 2006

The genetic toxicity of environmental pollutants, namely, nonylphenol (NP), bisphenol A (BPA) and chloropyriphos (CP) was investigated in aquatic sentinel species, freshwater crustacean, Daphnia magna, and larva of aquatic midge, Chironomus tentans, using Comet assay. Physiological effect of such pollutants was also investigated by studying the specimens' rates of reproduction, growth and survival. Acute toxicity results showed that, as expected, Daphnia was more sensitive than Chironomus to chemical exposure. The order of acute toxicity was CP > NP > BPA in D. magna and NP > CP > BPA in C. tentans. BPA may exert a genotoxic effect on D. magna and C. tentans, given that DNA strand breaks increased in both species exposed to this compound, whereas NP- and CP-induced DNA damage occurred only in C. tentans. In vivo genotoxic data obtained in aquatic sentinel species could provide valuable information for freshwater quality monitoring. The experiments with NP-exposed D. magna showed that the pollutant has long-term effects on reproduction, whereas no short-term effect on DNA integrity was found, being an example of a false-negative result from the biomarkers perspective. This result could be interpreted that other mechanism than genetic alteration might be involved in NP-induced reproduction failure in D. magna. False-positive results from the genotoxic biomarker obtained in BPA-exposed D. magna and in NP-exposed C. tentans make it difficult to use DNA integrity as an early warning biomarker. However, as the mere presence of genotoxic compounds, which are potentially carcinogenic, is of high concern to human and ecosystem health, it could also be important to rapidly and effectively detect genotoxic compounds in the aquatic system in ways that do not necessarily accompany a higher level of alteration. Considering the potential of D. magna and C. tentans as bioindicator species, and the importance of genotoxic biomarkers in ecotoxicity monitoring, DNA damage in these species could provide useful information for environmental risk assessment.

• Archives of Pharmacal Research
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• v.17 no.3
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• pp.199-203
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• 1994

Several lines evidence indicate that microtubule depolymerization initiates DNA synthesis or enhances the effects of serum or purified growth factors in many types of fibroblasts. Yet little is known about the intracellular events responsible for the mitogenic effect of microtubule disrupting agents. The effects of antitubulin agents on DNA synthesis in sparse and dense cultures in the presence or absence of serum and possible involvement of G-proteins in their mitotic action were examined. In these studies, colchicine by itself appeared to be mitogenic only for confluent quiesecent human lung fibroblasts. In sparse culture, however, colchicine inhibited serum-stimulated DNA synthesis. Colcemid, another antitubulin agent, showed similar effects of growth inhibition and stimulation in sparse and confluent cultures while lumicolhicine, inactive colchicine, did not. The mitogenic effect of two antitubulin agents, colchicine and colcemid, was partially inhibited by pertussis toxin. These data suggest that microtubular integrity is associated with the expression of either negative or positive control on DNA synthesis and mitogenic effect of antitubulin agents may be partially mediated by pertussis toxin-sensitive G protein.