• 생명과학회지
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• 제25권8호
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• pp.925-931
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• 2015

미립 품질 향상을 위하여 미립 형태를 결정하는 특성을 위한 분자육종기술을 확립하기 위하여 미립과 관련된 양적형질 유전자좌를 탐색하고, 이들 환경요인과 상호작용 효과를 분석한 결과는 다음과 같다. 인디카 품종인 ‘청청’과 자포니카형인 ‘낙동’이 교배된 조합 F₁의 약배양에 의해 양성된 120 계통(DH 집단)과 217개의 DNA 마커를 이용하여 전체 길이가 2,067cM이고, 마커간 평균거리가 9.5cM인 유전자 지도를 작성하였다. 미립형태 관련 유전자좌 분석에서 미립의 외형인 길이, 폭, 두께, 장폭비, 천립중과 관련하여 14개의 QTL이 탐색되었다. 현미의 미립길이 관련 3개의 QTL (qGL2, qGL5, qGL7), 미립 폭 관련 3개의 QTL (qGW2-1, qGW2-2, qGW2-3), 미립 두께 관련 1개의 QTL (qGT2), 장폭비 관련 6개의 QTL (qLWR2-1, qLWR2-2, qLWR2-3, qLWR2-4, qLWR7, qLWR12) 및 천립중 관련 1개의 QTL (qTGW8)이 선발되었다. 미립 장폭비 관련 4개의 QTL은 미립길이와 미립두께에서 동일한 염색체 상에서 확인되었다. 본 연구에서 구명된 QTL 마커들은 쌀 품종개량을 위하여 이용될 수 있을 것이라 판단된다.

• Journal of Animal Science and Technology
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• 제44권1호
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• pp.31-38
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• 2002

양적형질 유전자좌위(Quantitative trait loci; QTL) 연관지도 작성을 위해 regression interval mapping method에 의해 Berkshire종과 Yorkshire종간 교배를 통해 생산된 $F_2$ 집단에서 실시하였다. 염색체내 QTL 위치를 결정하기 위해 regression 모델을 통해 계산된 검정통계량(F-statistic)에 대한 유의적인 threshold 수준의 설정은 permutation test 및 Lander와 kruglyak (1995)에 의해 제시된 방법으로 산출하였다. 525두 $F_2$ 개체에 대해 조사된 기록 중 5형질(도체중, 등심 단면적, 근내지방 교잡도, 콜레스테롤 함량, 척추 늑골 등지방 두께) 기록을 분석에 이용하였고 genome 전체에 걸친 125개의 microsatellite marker에 대해 3세대 집단 모두 개체에 대해 유전자형을 조사하였다. 회귀분석 모형에 따라 additive 및 dominance 효과를 추정하였으며 이때 모든 회귀계수 값과 F-검정 통계량은 각각 1cM 단위로 추정하였다. 각 형질별, 염색체별로 10,000회의 permutation에 의해 genome-wise 및 chromosome-wise threshold를 추정하였다. Lander와 Kruglyak(1995)에 의해 제시된 방법으로 산출된 threshold 값은 매우 높게 추정되어 이러한 threshold의 적용시 실제로 QTL 존재 여부를 인정할 수 있는 경우의 수가 permutation에 의해 유도된 threshold를 적용했을 때보다 상대적으로 적은 결과를 보였다. 5% genome-wise threshold의 경우 형질별로 다소 상이한 경향을 나타냈으며 분석에 활용된 5개 형질에 대해 총 4개의 QTL이 5% genome-wise 수준에서 검색되었다.

• 한국육종학회지
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• 제41권4호
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• pp.456-462
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• 2009

본 연구는 최근 우리나라에서 급격하게 발생되고 있는 콩 불마름병에 대한 저항성 중간모본을 육성하고자 할 때 marker-assisted selection에 적용할 수 있는 저항성 근접 분자표지를 개발하고자 수행하였다. 1. 불마름병에 이병성인 큰올콩과 저항성인 신팔달콩의 RIL 116 계통에 대하여 콩 불마름병 균주 8ra에 대한 저항성과 연관된 QTL을 탐색한 결과 포장에서는 연관군 B2, D2, I와 K에서, 온실에서는 연관군 D2, C1과 F에서 불마름병과 관련된 QTL이 나타났다. 2. 포장과 온실에서 공통적으로 탐색된 QTL은 연관군 D2에 위치해 있었는데 정확한 위치는 포장과 온실에서 각각 Satt135와 Satt397의 사이에서 LOD score 6.64와 3.43으로 Satt135에서 14.01 cM과 0.01 cM 떨어진 위치에서 탐색되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권10호
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• pp.1359-1365
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• 2009

We performed a genome-wide linkage and quantitative trait locus (QTL) analysis to confirm the existence of QTL affecting Rous Sarcoma Virus (RSV) induced tumor regression, and to estimate their effects on phenotypic variance in an F2 resource population. The F2 population comprised 158 chickens obtained by crossing tumor regressive White Leghorn (WL) and tumor progressive Rhode Island Red (RIR) lines was measured for tumor formation after RSV inoculation. Forty-three tumor progressive and 28 tumor regressive chickens were then used for genome-wide linkage and QTL analysis using a total of 186 microsatellite markers. Microsatellite markers were mapped on 20 autosomal chromosomes. A significant QTL was detected with marker LEI0258 located within the MHC B region on chromosome 16. This QTL had the highest F ratio (9.8) and accounted for 20.1% of the phenotypic variation. Suggestive QTL were also detected on chromosomes 4, 7 and 10. The QTL on chromosome 4 were detected at the 1% chromosome-wide level explaining 17.5% of the phenotypic variation, and the QTLs on chromosome 7 and 10 were detected at the 5% chromosome-wide level and explained 11.1% and 10.5% of the phenotypic variation, respectively. These results indicate that the QTLs in the non-MHC regions play a significant role in RSV-induced tumor regression. The present study constitutes one of the first preliminary reports in domestic chickens for QTLs affecting RSV-induced tumor regression outside the MHC region.

• Asian-Australasian Journal of Animal Sciences
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• 제23권3호
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• pp.287-291
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• 2010

The purpose of this study was to detect quantitative trait loci (QTL) for growth and carcass quality traits on BTA6 in a population of Hanwoo cattle. Three hundred and sixty one steers were produced from 39 sires that were sired by 17 grandsires in the two Hanwoo farming branches of the National Livestock Research Institute of Korea, between Spring 2000 and Fall 2002. DNA samples were collected for all of the steers, sires and grandsires, and the phenotypes for six growth and carcass quality traits were measured at 24 months of age. Twelve microsatellite markers were chosen on BTA6 and a linkage map was constructed by using seven of the twelve markers. Then, a chromosome-wide QTL scan was performed by applying an Animal Model, in which effects of QTL alleles within the grand sires were fitted as a random term. Three QTL were detected at the 5% chromosome-wise level for backfat thickness, average daily gain, and final weight. The most likely positions for the QTL were in the proximal region, i.e. 0 cM, 35 cM, and 63 cM, respectively. Also, another QTL for longissimus dorsi muscle area was detected at the 10% chromosome-wise level at 67 cM. These results were, in general, consistent with our previous report, in which candidate gene analyses showed that a SNP near ILSTS035 flanked by BM4621 (62.5 cM) and BMS2460 (81.3 cM) was associated with final weight, carcass weight, average daily gain, and longissimus dorsi muscle area in the same Hanwoo population.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.148-148
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• 2017

Soybean is an important economical resource of protein and oil for human and animals. The genetic basis of seed protein and oil content has been separately characterized in soybean. However, the genetic relationship between seed protein and oil content remains to be elucidated. In this study, we used a combined analysis of phenotypic correlation and linkage mapping to dissect the relationship between seed protein and oil content. A $F_{10:11}$ RIL population containing 222 lines, derived from the cross between two Korean soybean cultivars Seadanbaek as female and Neulchan as male parent, were used in this experiment. Soybean seed analyzed were harvested in three different experimental environments. A genetic linkage map was constructed with 180K SoyaSNP Chip and QTLs of both traits were analyzed using the software QTL IciMapping. QTL analyses for seed protein and oil content were conducted by composite interval mapping across a genome wide genetic map. This study detected four major QTL for oil content located in chromosome 10, 13, 15 and 16 that explained 13.2-19.8% of the phenotypic variation. In addition, 3 major QTL for protein content were detected in chromosome 10, 11 and 16 that explained 40.8~53.2% of the phenotypic variation. A major QTLs was found to be associated with both seed protein and oil content. A major QTL were mapped to soybean chromosomes 16, which were designated qHPO16. These loci have not been previously reported. Our results reveal a signi cant genetic relationship between seed protein and oil fi content traits. The markers linked closely to these major QTLs may be used for selection of soybean varieties with improved seed protein and oil content.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1087-1092
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• 2003

As an experimental reference population, crosses between Korean native pig and Landraces were established and information on growth traits was recorded. Animals were genotyped for 24 microsatellite markers covering chromosomes 2, 6, and 7 for partial-genome scan to identify chromosomal regions that have effects on growth traits. quantitative trait loci (QTL) effects were estimated using interval mapping by the regression method under the line cross models with a test for imprinting effects. For test of presence of QTL, chromosome-wide and single position significance thresholds were estimated by permutation test and normal significance threshold for the imprinting test were derived. For tests against the Mendelian model, additive and dominance coefficients were permuted within individuals. Thresholds (5% chromosome-wide) against the no-QTL model for the analyzed traits ranged from 4.57 to 4.99 for the Mendelian model and from 4.14 to 4.67 for the imprinting model, respectively. Partial-genome scan revealed significant evidence for 4 QTL affecting growth traits, and 2 out of the 4 QTLs were imprinted. This study demonstrated that testing for imprinting should become a standard procedure to unravel the genetic control of multi-factorial traits. The models and tests developed in this study allowed the detection and evaluation of imprinted QTL.

• Asian-Australasian Journal of Animal Sciences
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• 제23권10호
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• pp.1261-1267
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• 2010

Milk production traits are important economic traits for dairy cattle. The aim of the present study was to refine the position of previously detected quantitative trait loci (QTL) on bovine chromosome 6 affecting milk production traits in Chinese Holstein dairy cattle. A daughter design with 918 daughters from 8 elite sire families and 14 markers spanning the previously identified QTL region were used in the analysis. We employed a combined linkage and linkage disequilibrium analysis (LDLA) approach with two options for calculating the IBD probabilities, one was based on haplotypes of all 14 markers (named Method 1) and the other based on haplotypes with sliding windows of 5 markers (named Method 2). For milk fat yield, the two methods revealed a highly significant QTL located within a 6.5 cM interval (Method 1) and a 4.0 cM interval (Method 2), respectively. For milk protein yield, a highly significant QTL was detected within a 3.0 cM interval (Method 1) or a 2.5 cM interval (Method 2). These results confirmed the findings of our previous study and other studies, and greatly narrowed down the QTL positions.

• 한국작물학회지
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• 제55권2호
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• pp.105-110
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• 2010

도복과 관련된 주요 형질인 초장, 3절간장, 좌절중 등에 대한 QTL을 분석을 수행하였으며 도복과 벼멸구 저항성과의 연관 관계에 대한 QTL 및 유의성을 분석하였다. 1. 초장, 3절간장, 모멘트, 도복지수, 좌절중과 같은 도복관련 형질에 대한 QTL을 분석하여 총 13개의 유의성 있는 QTL이 6개의 염색체상에서 확인되었다. 2. 벼멸구 저항성과 주요 농업형질관련 QTL과의 연관관계를 분석한 바, 7번과 8번 염색체 상의 qBPR7, qBPR8은 각각 모멘트(qMo7)와 도복(q3rdin8) 관련 QTL에 연관되어 있었다. 3. Mapping 집단을 저항성 계통군과 감수성 계통군으로 나누어 8개 형질에 대한 차이를 조사한 바, 3절간장과 도복 지수에서 두 집단간에 유의성이 인정되었다. 4. 저항성을 가지는 계통은 간장 및 3절간장 등이 ‘삼강’의 영향으로 ‘낙동’에 비하여 짧은 경향이었으며 이는 신장과 관련된 도복성향에 있어 본 집단에서는 벼멸구 저항성이 강하게 연관이 되었다는 분석결과를 찾을 수 없었다.

• 한국육종학회지
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• 제42권2호
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• pp.144-150
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• 2010

The objective of this study was to map gene/QTL for photoblastism in a weedy rice (photoblastic rice: PBR) using DNA markers. Light-induced effect on germination of seeds was compared among three accessions (Oryza sativa L.), PBR, Milyang 23 and Ilpum. Results showed that PBR seeds started to show photoblastism during seed development, different from Ilpum and Milyang 23. Frequency distribution of germination in the F4 lines from crosses between Ilpum and PBR and, Milyang 23 and PBR revealed bimodal distributions suggesting that photoblastism was controlled by a few genes. Bulked segregant analysis using $F_4$ populations derived from the above two crosses was conducted to identify gene/QTL for photoblastism. Two QTL were identified on chromosomes 1 and 12 explaining 11.2 and 12.8% of the phenotypic variance, respectively. Two QTL were further mapped between two SSR markers, RM8260 and RM246 on chromosome 1, and between RM270 and 1103 on chromosome 12. It is noteworthy that two QTL for photoblastism were colocalized with the QTL for seed dormancy reported in the previous QTL studies. The clustering of two genes for photoblastism and dormancy possibly indicates that these regions constitute rice phytochrome gene clusters related to germination. Because PBR has a low degree of dormancy, a pleiotropic effect of a single gene controlling dormancy and photoblastism can be ruled out. The linked markers will provide the foundation for positional cloning of the gene.