• Journal of Plant Biotechnology
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• 제43권3호
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• pp.272-280
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• 2016

국화는 관상용, 약용으로 활용되는 주요한 화훼 작물중의 하나이다. 국화의 육종 프로그램은 다양한 품종의 개발에 기여하였으나, 다른 주요한 식량, 채소작물에서 보여졌듯이 전통적인 표현형 기반의 품종선발에서 분자표지를 활용한 선발로 진일보할 필요가 있다. 이러한 분자육종은 유전학, 분자생물학, 최근에는 유전체 연구로 규명된 형질연관 분자표지에 의존한다. 그러나 자가불화합성, 자식약세, 이질육배체, 이형접합성, 거대한 유전체와 같은 국화의 생식적, 유전적, 유전체의 특성으로 인하여 이러한 연구는 심각하게 지연되고 있다. 그럼에도 불구하고 유전연구를 통하여 국화의 유전자지도가 구축되었고 꽃, 잎, 식물구조와 같은 국화의 주요한 형질과 연관된 분자표지가 규명되었다. 염기서열 분석기술이 발달됨에 따라 국화의 전사체가 해독되어 국화의 표준유전자 목록이 구축되고 발달단계에 따라 혹은 생물적 비생물적 환경에서 특이적으로 발현되는 유전자도 규명되었다. 또한 2배체인 야생의 국화속 식물의 유전체 해독 프로젝트가 시작되었다. 이러한 대량의 염기서열 정보는 국화의 분자육종을 위한 근원적인 자원으로 활용될 수 있을 것이다. 이 총설에서는 국화의 분자유전학, 유전체 연구의 현황을 요약하고 향후 전망을 논의한다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1537-1544
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• 2015

Meat and carcass quality attributes are of crucial importance influencing consumer preference and profitability in the pork industry. A set of 400 Berkshire pigs were collected from Dasan breeding farm, Namwon, Chonbuk province, Korea that were born between 2012 and 2013. To perform genome wide association studies (GWAS), eleven meat and carcass quality traits were considered, including carcass weight, backfat thickness, pH value after 24 hours (pH24), Commission Internationale de l'Eclairage lightness in meat color (CIE L), redness in meat color (CIE a), yellowness in meat color (CIE b), filtering, drip loss, heat loss, shear force and marbling score. All of the 400 animals were genotyped with the Porcine 62K SNP BeadChips (Illumina Inc., USA). A SAS general linear model procedure (SAS version 9.2) was used to pre-adjust the animal phenotypes before GWAS with sire and sex effects as fixed effects and slaughter age as a covariate. After fitting the fixed and covariate factors in the model, the residuals of the phenotype regressed on additive effects of each single nucleotide polymorphism (SNP) under a linear regression model (PLINK version 1.07). The significant SNPs after permutation testing at a chromosome-wise level were subjected to stepwise regression analysis to determine the best set of SNP markers. A total of 55 significant (p<0.05) SNPs or quantitative trait loci (QTL) were detected on various chromosomes. The QTLs explained from 5.06% to 8.28% of the total phenotypic variation of the traits. Some QTLs with pleiotropic effect were also identified. A pair of significant QTL for pH24 was also found to affect both CIE L and drip loss percentage. The significant QTL after characterization of the functional candidate genes on the QTL or around the QTL region may be effectively and efficiently used in marker assisted selection to achieve enhanced genetic improvement of the trait considered.

• Asian-Australasian Journal of Animal Sciences
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• 제25권11호
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• pp.1529-1539
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• 2012

A whole genome association (WGA) study was performed to detect significant polymorphisms for meat quality traits in an $F_2$ cross population (N = 478) that were generated with Korean native pig sires and Landrace dams in National Livestock Research Institute, Songwhan, Korea. The animals were genotyped using Illumina porcine 60k SNP beadchips, in which a set of 46,865 SNPs were available for the WGA analyses on ten carcass quality traits; live weight, crude protein, crude lipids, crude ash, water holding capacity, drip loss, shear force, CIE L, CIE a and CIE b. Phenotypes were regressed on additive and dominance effects for each SNP using a simple linear regression model, after adjusting for sex, sire and slaughter stage as fixed effects. With the significant SNPs for each trait (p<0.001), a stepwise regression procedure was applied to determine the best set of SNPs with the additive and/or dominance effects. A total of 106 SNPs, or quantitative trait loci (QTL) were detected, and about 32 to 66% of the total phenotypic variation was explained by the significant SNPs for each trait. The QTL were identified in most porcine chromosomes (SSCs), in which majority of the QTL were detected in SSCs 1, 2, 12, 13, 14 and 16. Several QTL clusters were identified on SSCs 12, 16 and 17, and a cluster of QTL influencing crude protein, crude lipid, drip loss, shear force, CIE a and CIE b were located between 20 and 29 Mb of SSC12. A pleiotropic QTL for drip loss, CIE L and CIE b was also detected on SSC16. These QTL need to be validated in commercial pig populations for genetic improvement in meat quality via marker-assisted selection.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.322-329
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• 2011

A whole genome association (WGA) study was conducted to identify quantitative trait loci (QTL) for body conformation traits in Hanwoo cattle. The phenotypes of 497 steers were recorded from the Hanwoo Improvement Center of National Agricultural Cooperative Federation, Seosan, Korea, and analyzed using the Illumina Bovine 50 k SNP chip. A set of 35,987 SNPs that were available in the Hanwoo population was selected from the chip. After adjustments for the effects of year-season of birth, region and sire, phenotypes were regressed on each SNP using a linear regression model. Three hundred nineteen SNPs were detected for the ten conformation traits (p<0.003). For the significant SNPs, stepwise regression procedures were applied to determine best sets of markers. A total of 72 SNPs were selected (p<0.001), for which the sets of 5, 9, 10, 9, 8, 11, 4, 6, 3 and 7 SNPs were determined for height at withers, rump height, body length, chest depth, chest width, rump length, hip width, thurl width, pinbone width and heart girth, respectively. About 7-26% of the total phenotypic variation was explained by the set of SNPs for each trait. QTL for the conformation traits were harbored on most bovine chromosomes (BTAs). Four SNPs with pleiotropic effects on height at withers and rump height were detected on BTAs 3, 4, 6 and 16. A SNP with pleiotropic effects on chest width and rump length was also detected on BTA10. Two QTL regions, i.e. between 87 and 97 Mb in BTA3 and between 41 and 44 Mb in BTA7, were found, in which SNPs were detected for the five and three conformation traits, respectively. The detected SNPs need to be validated in other Hanwoo populations for commercial application to the genetic improvement of conformation characteristics in Hanwoo via marker-assisted selection (MAS).

• Asian-Australasian Journal of Animal Sciences
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• 제31권4호
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• pp.480-488
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• 2018

Objective: Average daily gain (ADG) is an important target trait of pig breeding programs. We aimed to identify single nucleotide polymorphisms (SNPs) and genomic regions that are associated with ADG in the Duroc pig population. Methods: We performed a genome-wide association study involving 390 Duroc boars and by using the PorcineSNP60K Beadchip and two linear models. Results: After quality control, we detected 3,5971 SNPs, which included seven SNPs that are significantly associated with the ADG of pigs. We identified six quantitative trait loci (QTL) regions for ADG. These QTLs included four previously reported QTLs on Sus scrofa chromosome (SSC) 1, SSC5, SSC9, and SSC13, as well as two novel QTLs on SSC6 and SSC16. In addition, we selected six candidate genes (general transcription factor 3C polypeptide 5, high mobility group AT-hook 2, nicotinamide phosphoribosyltransferase, oligodendrocyte transcription factor 1, pleckstrin homology and RhoGEF domain containing G4B, and ENSSSCG00000031548) associated with ADG on the basis of their physiological roles and positional information. These candidate genes are involved in skeletal muscle cell differentiation, diet-induced obesity, and nervous system development. Conclusion: This study contributes to the identification of the casual mutation that underlies QTLs associated with ADG and to future pig breeding programs based on marker-assisted selection. Further studies are needed to elucidate the role of the identified candidate genes in the physiological processes involved in ADG regulation.

• Plant Breeding and Biotechnology
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• 제6권4호
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• pp.391-403
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• 2018

Genome resequencing by next-generation sequencing technology can reveal numerous single nucleotide polymorphisms (SNPs) within a closely-related cultivar group, which would enable the development of sufficient SNP markers for mapping and the identification of useful genes present in the cultivar group. We analyzed genome sequence data from 13 Korean japonica rice varieties and discovered 740,566 SNPs. The SNPs were distributed at 100-kbp intervals throughout the rice genome, although the SNP density was uneven among the chromosomes. Of the 740,566 SNPs, 1,014 SNP sites were selected on the basis of polymorphism information content (PIC) value higher than 0.4 per 200-kbp interval, and 506 of these SNPs were converted to Kompetitive Allele-Specific PCR (KASP) markers. The 506 KASP markers were tested for genotyping with the 13 sequenced Korean japonica rice varieties, and polymorphisms were detected in 400 KASP markers (79.1%) which would be suitable for genetic analysis and molecular breeding. Additionally, a genetic map comprising 205 KASP markers was successfully constructed with 188 $F_2$ progenies derived from a cross between the varieties, Junam and Nampyeong. In a phylogenetic analysis with 81 KASP markers, 13 Korean japonica varieties showed close genetic relationships and were divided into three groups. More KASP markers are being developed and these markers will be utilized in gene mapping, quantitative trait locus (QTL) analysis, marker-assisted selection and other strategies relevant to crop improvement.

• Animal Bioscience
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• 제36권6호
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• pp.861-868
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• 2023

Objective: Loin muscle area (LMA) is an important target trait of pig breeding. This study aimed to identify single nucleotide polymorphisms (SNPs) and genes associated with LMA in the Duroc×(Landrace×Yorkshire) crossbred pigs (DLY). Methods: A genome-wide association study was performed using the Illumina 50K chip to map the genetic marker and genes associated with LMA in 511 DLY pigs (255 boars and 256 sows). Results: After quality control, we detected 35,426 SNPs, including six SNPs significantly associated with LMA in pigs, with MARC0094338 and ASGA0072817 being the two key SNPs responsible for 1.77% and 2.48% of the phenotypic variance of LMA, respectively. Based on previous research, we determined two candidate genes (growth hormone receptor [GHR] and 3-oxoacid Co A-transferase 1 [OXCT1]) that are associated with fat deposition and muscle growth and found further additional genes (MYOCD, ARHGAP44, ELAC2, MAP2K4, FBXO4, FBLL1, RARS1, SLIT3, and RANK3) that are presumed to have an effect on LMA. Conclusion: This study contributes to the identification of the mutation that underlies quantitative trait loci associated with LMA and to future pig breeding programs based on marker-assisted selection. Further studies are needed to elucidate the role of the identified candidate genes in the physiological processes involved in LMA regulation.

• 원예과학기술지
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• 제30권5호
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• pp.557-567
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• 2012

본 연구는 마커이용여교잡(marker-assisted backcross, MAB)을 통한 내병성 토마토 신품종육성에 필요한 기초 정보를 얻기 위해 수행되었다. TYLCV, 시들음역병, 청고병, 흰가루병에 내병성인 공여친 계통 10종과 이병성이지만 우수 원예형질을 지닌 회복친 계통 4종에 대해 병리검정과 TYLCV 내병성 연관 분자마커 분석을 수행하였다. MAB를 위한 회복친 유전자 선발(background selection)용 마커개발을 목표로 SOL Genomics Network에 공시된 토마토 유전자지도(reference map)로부터 전 게놈에 균등히 분포된 108개(염색체 당 평균 9개) SSR 마커를 분석하여, 총 303개의 다형성 마커를 기반으로 공여친, 회복친 계통 간 유연관계를 분석하였다. 그 결과, 유사도 값의 전체 범위는 0.33-0.80으로계통 간 가장 높은 유사도 값(0.80)을 나타낸 것은 청고병에 저항성인 '10BA333'와 '10BA424'이었고, 가장 낮은 유사도 값(0.33)을 나타낸 것은 시들음역병에 내병성인 야생종 L3708(Solanum pimpinelliforium L.)과 청고병에 저항성인 '10BA424'이었다. 유사도 값을 이용하여 UPGMA 분석한 결과, 유사도 0.58를 기준으로 나누었을 때 3개의 군(cluster)으로 분류되었는데, 대부분 동일한 내병성을 지닌 공여친계통 간 유전적 거리가 가까워 이들은 공통된 저항성 재료를 이용한 육성과정에서 파생된 계통일 것이라 판단되었다. 계통수(dendrogram)를 기준으로 유전적 거리가 지나치게 멀지 않으면서 비교적 다수의 회복친 유전자 선발용 SSR 마커의 확보가 가능한 여교배 조합(공여친 ${\times}$ 회복친)은 TYLCV 내병성의 경우 'TYR1' ${\times}$ 'RPL1', 청고병의 경우 '10BA333' 또는 '10BA424' ${\times}$ 'RPL2', 흰가루병의 경우 'KNU12' ${\times}$ 'AV107-4' 또는 'RPL2'로 판단되었다. 시들음역병의 경우 내병성 공여친인 'L3708'은 야생종으로서 모든 회복친 계통들과 유전적 거리가 매우 멀었으며, 적절한 조합은 유사도 값이 0.41이며 계통 간 45개의 다형성 SSR 마커가 선발된 'L3708' ${\times}$ 'AV107-4'로 판단되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권12호
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• pp.1651-1659
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• 2011

This study was conducted to detect quantitative trait loci (QTL) for thirteen growth and meat quality traits in pigs by combing QTL experimental populations. Two F2 reference populations that were sired by Korea native pig (KNP) and dammed by Landrace (LN) or Yorkshire (YK) were generated to construct linkage maps using 123 genetic markers (mostly microsatellites) and to perform QTL analysis on porcine chromosomes (SSCs) 1, 2, 3, 6, 7, 8, 9, 11, 13, 14, and 15. A set of line-cross models was applied to detect QTL, and a series of lack-of-fit tests between the models was used to characterize inheritance mode of QTL. A total of 23, 11 and 19 QTL were detected at 5% chromosome-wise level for the data sets of KNP${\times}$LN, KNP${\times}$YK cross and joint sets of the two cross populations, respectively. With the joint data, two Mendelian expressed QTL for live weight and cooking loss were detected on SSC3 and SSC15 at 1% chromosome-wise level, respectively. Another Mendelian expressed QTL was detected for CIE a on SSC7 at 5% genome-wise level. Our results suggest that QTL analysis by combining data from two QTL populations increase power for QTL detection, which could provide more accurate genetic information in subsequent marker-assisted selection.

• Mycobiology
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• 제45권2호
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• pp.105-109
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• 2017

Sixteen genomic DNA simple sequence repeat (SSR) markers of Lentinula edodes were developed from 205 SSR motifs present in 46.1-Mb long L. edodes genome sequences. The number of alleles ranged from 3-14 and the major allele frequency was distributed from 0.17-0.96. The values of observed and expected heterozygosity ranged from 0.00-0.76 and 0.07-0.90, respectively. The polymorphic information content value ranged from 0.07-0.89. A dendrogram, based on 16 SSR markers clustered by the paired hierarchical clustering' method, showed that 33 shiitake cultivars could be divided into three major groups and successfully identified. These SSR markers will contribute to the efficient breeding of this species by providing diversity in shiitake varieties. Furthermore, the genomic information covered by the markers can provide a valuable resource for genetic linkage map construction, molecular mapping, and marker-assisted selection in the shiitake mushroom.