1, 2, 4-Benzenetriol에 의해 유도된 HL-60 세포의 DNA 손상

정해원(Hai Won Chung),김선진(Sun Jin Kim),최영주(Young Joo Choi),김수영(Su Young Kim) 한국환경보건학회 2000 한국환경보건학회지 Vol.26 No.1

One of the carcinogenic mechanisms of benzene is believed to be the oxidative damage caused by its metabolites. The triphenolic metabolite of benzene, 1,2,4-benzenetriol(BT) is readily oxidized to its corresponding quinone via semiquinone radical. During this process reactive oxygen species are formed that may damage cellular DNA and induce genotoxic effects. A comparative study was carried out to examine the effect of BT on DNA damage by single cell gel electrophoresis assay(SCGE), chromosome aberration and lipid peroxidation production analysis. HL-60 cells were exposed to BT for 3 hours and the extent of DNA migration was measured by a single cell gell electrophoresis under alkaline conditions. BT induced DNA damage in a dose-dependent manner at concentrations between 10 μM and 100 μM and most of the cell could repair DNA damage inunediately following exposure to the chemical. BT also induced chromosome aberration and most frequent type of chromosome aberration is chromatid breaks. BT induced lipid peroxidation production. From above results, it is suggested that BT can induce DNA damage and chromosome aberration through production of reactive oxygen species(ROS).

3-Amino benzamide 및 Cytosine arabinoside가 방사선 조사된 림프구의 이동원 염색체 및 상호전좌 유발빈도에 미치는 영향

정해원(Hai Won Chung),김수영(Su Young Kim),조윤희(Yoon Hee Cho),김태환(Tae Hwan Kim),조철구(Chul Koo Cho),하성환(Sung Hwan Ha) 한국환경성돌연변이발암원학회 2002 한국환경성돌연변이·발암원학회지 Vol.22 No.3

In irradiated human lymphocytes, translocation of chromosome has been more frequently observed than dicentric chromosome. Differences in the misrepair process leading to translocation and dicentric chromosomes may explain the above observations. In order to find out whether dicentric and translocation are originated from different mechanism, the frequencies of radiation induced translocation and dicentric in lymphocytes were examined following treatment of irradiated lymphocytes with two DNA repair inhibitors, 3AB for inhibition of poly(ADP-ribose) synthesis and Ara C for inhibition of DNA-polymerase α. Ara C potentiated the frequencies of radiation induced dicentric and translocation. 3AB also potentiated the frequencies of radiation induced dicentric, but not translocation. These results suggest the potential differences in the mechanisms in the formation of translocation and dicentric chromosomes.

FISH기법 및 단세포전기영동기법을 이용한 저선량 방사선에 의한 DNA 상해 및 염색체이상 평가

정해원,김수영,김병모,김선진,김태환,조철구,하성환,Chung, Hai-Won,Kim, Su-Young,Kim, Byung-Mo,Kim, Sun-Jin,Kim, Tae-Hwan,Cho, Chul-Koo,Ha, Sung-Whan 대한방사선방어학회 2000 방사선방어학회지 Vol.25 No.4

단세포전기영동법은 저선량 방사선에 의한 DNA손상을 민감하게 측정할 수 있는 방법으로 그 활용성이 증대되고 있다. 또한 각 염색체에 특이한 DNA probe를 이용하는 FISH기법은 염색체의 구조적 변화를 측정하는 매우 효과적인 방법으로서 그 유용성이 증대되고 있는 추세이다. 본 연구에서는 저선량 방사선의 측정을 위한 생물학적 선량계로서 FISH 기법과 단세포전기영동법의 활용가능성을 조사하고자 하였다. 5, 10, 30, 및 50 cGy의 저선량 방사선 조사에 의한 염색체이상빈도는 상호전좌의 경우 1, 2, 4번 염색체가 전체 genome상에서 차지하는 비율을 감안하여, 전체 세포수로 환산했을 때 cell equivalent당 0.0375, 0.0407, 0.0727 및 0.0814로 나타났으며, 이동원염색체의 경우 0.0125, 0.0174, 0.02291, 및 0.0407로 나타나 선량 증가에 따라 증가하는 것을 알 수 있었다. 또한 $5{\sim}50cGy$의 저선량 방사선 조사 후 단세포전기영동법을 통해 DNA 상해정도를 살펴본 결과 선량이 증가할수록 DNA 상해가 증가하는 결과를 얻었다. 따라서 FISH 기법은 저선량 방사선 피폭시 염색체이상을 보다 정확하고 쉽게 관찰할 수 있으며, 단세포전기영동법은 DNA 손상을 민감하게 감지할 수 있어 저선략 방사선 피폭 시 유용한 생물학적 선량계로서 활용될 수 있을 것으로 기대된다. Comparative study was performed for the assessment of DNA damage and Chromosomal aberration in human lymphocyte exposed to low dose radiation using fluorescence in situ hybridization(FISH) and single cell gel electrophoresis(SCGE). Chromosomal aberrations in human lymphocytes exposed to radiation at doses of 5, 10, 30 and 50cGy were analysed with whole chromosome-specific probes by human chromosome 1, 2 and 4 according to PAINT system. FISH with chromosome-specific probe has been used to be a valid and rapid method fer detection of chromosome rearrangements induced by low dose radiation. The frequencies of stable translocation per cell equivalents were 0.0116, 0.0375, 0.040f, 0.0727 and 0.0814 for 0, 5, 10, 30 and 50cGy, respectively, and those of dicentric were 0.00, 0.0125, 0.174, 0.0291 and 0.0407 respectively. Radiation induced DNA damage in human lymphocyte in a dose-dependent manner at low doses from 5cGy to 50cGy, which were analysed by single tell gel electrophoresis(SCGE). From above results, FISH seemed to be useful for radiation biodosimetry by which the frequencies of stable aberrations in human lymphocyte can be observed more easily than by conventional method and SCGE also seemed to be sensitive method f9r detecting DNA damage by low dose radiation exposure, so that those methods will improve our technique to perform meaningful biodosimetry for radiation at low doses.

3중 DNA probe를 이용한 FISH(fluorescence in situ hybridization) 기법으로 방사선에 의한 염색체 이상 분석

정해원,김수영,하성환,Chung, Hai-Won,Kim, Su-Young,Ha, Sung-Whan 대한방사선방어학회 1999 방사선방어학회지 Vol.24 No.1

Fluorescence in situ hybridization with chromosome-specific probe has been shown to be a valid and rapid method for detection of chromosome rearrangements induced by radiation. This method is useful for quantifying structural aberrations, expecially for stable ones, such as translocation and insertion, which are difficult to detect with conventional method in human lymphocyte. In order to apply FISH method for high dose biological dosimetry, chromosomal abberations by radiation at doses of 1, 3, 5, and 7Gy were analysed with whole chromosome-specific probes by human chromosome 1, 2 and 4 according to PAINT system. The frequencies of stable translocation per cell equivalent were 0.04, 0.33, 1.22, 2.62, and 5.58 for the lymphocyte exposed to 0, 1, 3, 5, and 7Gy, respectively, and those of dicentric were 0.00, 0.06, 0.52, 1.19 and 2.44, respectively. Significantly more translocation of t(Ab), a translocated chromosome with a piece of painted acentric matrial 'b' attached to unpainted piece containing centromere 'A', than reciprocal chromosome t(Ba) was observed. The frequencies of all type of chromosome rearrangements increased with dose. From above result, FISH seemed to be useful for radiation biodosimetry by which the frequencies of various types of stable aberrations in human lymphocyte can be observed more easily than by conventional method and so will improve our ability to perform meaningful biodosimetry. 각 염색체에 특이한 DNA probe를 이용하는 FISH기법은 방사선에 의해 유발된 상호전좌 및 삽입 등의 염색체의 구조적 변화를 측정하는 매우 효과적인 방법으로서 그 활용성이 증가되고 있다. 본연구는 방사선 피폭시 생물학적 선량측정법으로서 FISH기법을 활용하기 위하여 사람의 1, 2, 4번 염색체에 특이한 probe를 이용하여 고선량 단일 피폭시 유발된 각종 염색체 이상빈도를 관찰하고 이를 PAINT분류체계에 의해 분석하였다. 방사선 조사에 의한 염색체 이상빈도는 상호전좌(t)와 이동원염색체(dic)의 수가 선량 증가에 따라 같이 증가하는 것을 알 수 있으며 color junction의 수도 선량에 따라 증가하는 것을 알 수 있었다. 상호전좌의 빈도는 이동원 염색체의 빈도보다 상대적으로 높게 나타났다. 삽입(ins), 무동원염색체(ace), 및 환상염색체(r)의 수도 선량 증가에 따라 같이 증가하는 것을 알 수 있었다. 기존의 염색체재배열 분석방법과 비교해 볼 때 FISH기법은 다양한 형태의 염색체재해열을 보다 쉽게 관찰할 수 있게 하며 생물학적 선량제로서 중요한 역할을 할 것이라 기대된다.

방사선에 의한 염색체이상과 DNA 함량과의 관계

정해원,김수영,하성환,김태환,조철구,Chung, Hai-Won,Kim, Su-Young,Ha, Sung-Whan,Kim, Tae-Hwan,Cho, Chul-Koo 대한방사선방어학회 2001 방사선방어학회지 Vol.26 No.2

본 연구는 염색체 1, 2, 4, 7, 8, 9 및 21번 염색체의 DNA probe를 이용하여 2Gy의 방사선을 조사한 후 DNA 양을 감안한 기대치와 관찰치의 차이를 비교함으로서 각 염색체의 방사선에 대한 감수성을 평가하여 궁극적으로 방사선 피폭시 생물학적 선량계로서 FISH기법의 타당성을 평가하고자 하였다. 1번 및 4번 염색체의 경우 상호전좌와 이동원 염색체의 관찰치가 기대치보다 더 높게 나타났으며 이와 반대로 2, 7, 8 및 9번 염색체의 경우 상호전좌와 이동원염색체의 관찰치 모두 기대치보다 낮게 나타났다. 2번 및 4번 염색체의 경우 1번 염색체보다 더 많은 acentric fragment의 빈도를 나타내었다. 1, 2, 및 4번 염색체 3종을 조합했을 때 상호전좌의 경우 관찰치와 기대치는 세포 100개당 25.5 및 25.40으로 차이가 없었으며 이동원염색체의 경우 13.25 및 13.2로 역시 거의 차이가 없게 나타났다. 따라서 본 연구결과 방사선 피폭시 발생하는 염색체이상 빈도는 염색체마다 DNA 양에 비례해 나타나지 않을 수 있어 각 염색체마다 방사선 감수성에 차이가 있을 것으로 판단된다. 또한 방사선 피폭시 생물학적 선량계로서 1, 2 및 4번을 동시에 관찰 할 경우 염색체 FISH 법을 활용하기 위하여 적절한 염색체 조합이라고 판단된다. To study the relationship between the DNA content of human chromosomes and their involvement in radiation-induced structural chromosome aberrations, the frequencies of translocations and dicentrics induced in human lymphocytes after in vitro exposure to 2Gy of x-tay were analysed by fluorescence in situ hybridization(FISH). Single whole chromosome probes(WCP), specific for chromosomes 1, 2, 4, 7, 8, 9, and 21 and triple combination of probes tot chromosome 1, 2 & 4 were used separately. A significant deviation of the frequency of symmetrical translocation and dicentrics from a DNA-proportional distribution was observed. Chromosomes 2, 7, 8, 9 and 21 were less frequently involved in the formation of symmetrical translocations and dicentrics than expected, whereas chromosomes 1 and 4 were more frequently involved. Chromosome 2 and 4 showed a higher frequency of acentric fragments. When triple combination probe for chromosome 1, 2 & 4 was used, no differences were found between the observed and expected frequency of exchange type aberrations. The results showed that the frequency of radiation-induced chromosome aberrations was not proportional to DNA contents, suggesting the difference in the susceptibility to specific aberrations among individual chromosomes. The results also indicated that the FISH technique with combination of probes for chromosome 1, 2 & 4 was useful for radiation biodosimetry.

GABA 함량이 증가된 현미 첨가 쿠키의 품질특성과 아미노산 함량

정해원(Hae Won Jung),정해정(Hai-Jung Chung) 한국식품영양과학회 2013 한국식품영양과학회지 Vol.42 No.11

본 연구에서는 현미가루를 밀가루 중량기준 0%, 20%, 40%, 60%의 비율로 첨가하여 쿠키를 제조하고 반죽의 밀도, pH, 쿠키의 일반성분, 퍼짐성, 손실률, 팽창률, 색도, 경도, GABA 및 아미노산 함량, 기호도 검사 등을 실시하였다. 수분함량은 첨가군이 대조군보다 높게 나타났고 조단백질 함량과 조지방 함량은 시료 간에 유의적인 차이를 나타내지 않았으며 조회분 함량은 60% 첨가군에서 가장 높게 나타났다. 쿠키 반죽의 밀도는 60% 첨가군이 가장 낮았고 pH는 가장 높았다. 퍼짐성은 헌미가루 첨가량이 증가할수록 대체적으로 감소하였고 손실률과 팽창률은 증가하는 경향을 나타내었다. 경도는 40% 첨가군과 60% 첨가군에서 낮게 나타났다. 밝기를 나타내는 L값은 대조군이 가장 높았고 a값은 현미가루 첨가량이 증가할수록 증가하였으며 b값은 감소하였다. 쿠키의 GABA 함량은 대조군이 가장 낮았고 현미가루 첨가량이 증가할수록 증가하여 60% 첨가군에서 가장 높게 나타났다. 총 아미노산 함량은 대조군이 가장 높게 나타났으나 쌀의 제1제한 아미노산인 lysine의 함량은 대조군이 가장 낮았고 첨가군에서 높게 나타났다. 쿠키의 기호도 검사 결과 표면색은 대조군보다 현미가루 첨가군이 낮은 점수로 평가된 반면 냄새, 맛, 조직감 및 전체적인 기호도는 모든 시료 간에 유의적인 차이가 없었다. 이와 같은 결과를 종합하여 볼 때 현미가루를 60%까지 첨가하여 제품화 한다면 대조군과 비교하여 관능성이 크게 저하되지 않으면서 GABA 함량이 증진되어 기능성이 향상된 쿠키가 될 것으로 사료된다. This study is conducted to investigate the quality characteristics of cookies containing different levels (0%, 20%, 40%, 60%) of brown rice powder with enhanced levels of GABA (γ-amino butyric acid). The pH of cookie dough was higher in cookies containing brown rice powder. A proximate composition analysis showed that the moisture content was increased with the addition of the brown rice powder, yet there was no significant difference in the crude protein and crude fat contents among the added groups. The ash content was the highest in the 60% added group. The spread factor of the control cookie was higher than that of cookies containing 40% and 60% brown rice powder. The incorporation of brown rice powder in cookies lowered the lightness and yellowness values, but increased the redness value. The hardness of the cookies was lower in 40% and 60% added groups than that of the controls. The GABA content in the brown rice added groups was higher than that of the control cookie, and increased as brown rice powder increased. A consumer acceptance test revealed that there was no significant difference in the overall preference scores among the cookies. From these findings, it is suggested that the cookies with brown rice powder up to 60% added can be developed as goods.

Benzo ( a ) pyrene diolepoxide 를 처리한 쥐 육종세포내의 DNA polymerase α및 β의 활성도의 변화

최준호,정해원,조철오 ( Joon Ho Choe,Hai Won Chung,Cheol O Joe ) 생화학분자생물학회 1990 BMB Reports Vol.23 No.1

Enzyme activities of DNA polymerase α and β have been analyzed in anti (+)-r-7, t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE) treated mouse sarcoma cells. The time courses of repair synthesis following treatment of mouse sarcoma cells with 400 ng/ml of BPDE as measured by ³H-thymidine incorporation into the cells for 1 hr show biphasic curve, which indicates two apparent repair phases. Two distinct chromatographic elution profiles of DNA polymerases were observed when cells were treated with carcinogen and post incubated for 3 or 9 hrs, and cell homogenates were applied onto DEAE-52 anion exchange column. Cellular level of DNA polymerase α activity allowed to repair the DNA damage for 3 hrs was significantly higher than that of DNA polymerase β while DNA polymerase β activity was a predominant one in 9 hrs post incubated cells. Data presented here suggest that both DNA polymerase α and β are required to resynthesize the excised DNA damage, and that DNA polymerase α is the major enzyme involved in the resynthesis of DNA damage after endonuclease nicking step while DNA polymerase β is playing the major role in filling the rest of the gap thereafter.

차세대 염기서열 분석 기법과 활용

권경훈 ( Kyoung Hun Kwon ),정해원 ( Hai Won Chung ) 서울대학교 인구의학연구소 2012 人口醫學硏究論集 Vol.25 No.-

The next generation sequencing (NGS) is faster and a lower cost new sequencing technique getting huge-large scale fragment, called reads, and sequence data than traditional sequencing. NGS technologies include a number of methods that are grouped broadly as template preparation, sequencing and imaging, and data analysis. Recently available next generation sequencer are the GS-FLX (Roche). Genome Analyzer (Illumina), and SOLiD (Life Technologies). However, the NGS produces much shorter sequences and large volumes of reads compared to conventional sequencing, whereby huge amounts of short reads are aligned onto a reference. For fast mapping of the massive amounts of short reads, a lot of mapping algorithms and programs have been developed. In this article, we introduce NGS technique and application of NGS.

분자유전진단 검사와 임상적용

권경훈 ( Kyung Hun Kwon ),정해원 ( Hai Won Chung ) 서울대학교 인구의학연구소 2008 人口醫學硏究論集 Vol.21 No.-

염색체 모자이시즘의 임상적 의의

권경훈 ( Kyoung Hun Kwon ),정해원 ( Hai Won Chung ) 서울대학교 인구의학연구소 2010 人口醫學硏究論集 Vol.23 No.-

Mosaicism is the presence of two or more chromosomally distinct cell lines, each seen in two or more cells. It arises after fertilization through inaccurate segregation of chromosomes at mitosis. Two mechanisms have been postulated to account for errors of segregation. Nondisjunction is the failure of the two chromatids to separate at the centromere at metaphase, causing both chromatids to go to the same daughter cell and leading to one hyperdiploid cell and one hypodiploid cell. Chromosome mosaicism is found in about 1% of amniotic fluid cell cultures. Mosaicism detected in amniotic fluid may represent the true mosaicism or may pseudomosaicism. If the same chromusome abnormality is seen in more than one cell and in two different cultures, it is considered a true mosaicism, whereas single-cell abnormalities from a single culture are regarded as pseudomosaicism. In this review, we describe a mosaicism in chromosome analysis, its diagnostic problems and clinical significance.