• Reproductive and Developmental Biology
• /
• 제28권2호
• /
• pp.107-112
• /
• 2004

Molecular genetic markers were genotyped used to detect chromosomal regions which contain economically important traits such as growth traits in pigs. Three generation resource population was constructed from a cross between the Korean native boars and Landrace sows. A total of 193 F2 animals from intercross of F1 were produced. Phenotypic data on 7 traits, birth weight, body weight at 3, 5, 12, 30 weeks of age, live empty weight were collected for F2 animals. Animals including grandparents (F0), parents (F1), offspring (F2) were genotyped for 194 microsatellite markers covering from chromosome 1 to 18. Quantitative trait locus analyses were performed using interval mapping by regression under line-cross model. To characterize presence of imprinting, genetic full model in which dominance, additive and imprinting effect were included was fitted in this analysis. Significance thresholds were determined by permutation test. Using imprinting full model, four QTL with expression of imprinted effect were detected at 5% chromosome-wide significance level for growth traits on chromosome 1, 5, 7, 13, 14, and 16.

• 한국작물학회지
• /
• 제48권1호
• /
• pp.56-64
• /
• 2003

If a quantitative trait loci (QTL) marker identified in a population is applicable to different populations (marker universality), this will not only reduce the labor and cost in marker assisted selection (MAS), but accelerate the application of molecular markers to real breeding programs. Present study aims to evaluate the defined QTL related markers from a population to a different breeding population for the MAS. Four rice breeding populations were subjected to seventy-five simple sequence repeat (SSR) markers which were already identified for their polymorphism information content (PIC) in the parents of the crossings. Among them, eight markers were evaluated for their correlation between presence of marker alleles and phenotypic expression in breeding populations. A reasonable level of polymorphism for the mapped markers originated from any sources of rice accessions was observed between crosses of any sources (marker repeatability). However, correlation between presence of markers and expression of the traits in rice breeding populations was not significant except for minor portion of traits and markers examined (failure of marker universality). In the present study, various strategies were discussed to develop new markers with universality of breeding application.

• Genomics & Informatics
• /
• 제12권4호
• /
• pp.187-194
• /
• 2014

Metabolic syndrome (METS) is a disorder of energy utilization and storage and increases the risk of developing cardiovascular disease and diabetes. To identify the genetic risk factors of METS, we carried out a genome-wide association study (GWAS) for 2,657 cases and 5,917 controls in Korean populations. As a result, we could identify 2 single nucleotide polymorphisms (SNPs) with genome-wide significance level p-values (< $5{\times}10^{-8}$), 8 SNPs with genome-wide suggestive p-values ($5{\times}10^{-8}{\leq}$ p < $1{\times}10^{-5}$), and 2 SNPs of more functional variants with borderline p-values ($5{\times}10^{-5}{\leq}$ p < $1{\times}10^{-4}$). On the other hand, the multiple correction criteria of conventional GWASs exclude false-positive loci, but simultaneously, they discard many true-positive loci. To reconsider the discarded true-positive loci, we attempted to include the functional variants (nonsynonymous SNPs [nsSNPs] and expression quantitative trait loci [eQTL]) among the top 5,000 SNPs based on the proportion of phenotypic variance explained by genotypic variance. In total, 159 eQTLs and 18 nsSNPs were presented in the top 5,000 SNPs. Although they should be replicated in other independent populations, 6 eQTLs and 2 nsSNP loci were located in the molecular pathways of LPL, APOA5, and CHRM2, which were the significant or suggestive loci in the METS GWAS. Conclusively, our approach using the conventional GWAS, reconsidering functional variants and pathway-based interpretation, suggests a useful method to understand the GWAS results of complex traits and can be expanded in other genomewide association studies.

• Asian-Australasian Journal of Animal Sciences
• /
• 제24권12호
• /
• pp.1644-1650
• /
• 2011

This study was conducted to detect quantitative trait loci (QTL) affecting meat quality in an $F_2$ reference population of Korean native pig and Landrace crossbreds. The three-generation mapping population was generated with 411 progeny from 38 $F_2$ full-sib families, and 133 genetic markers were used to produce a sex-average map of the 17 autosomes. The data set was analyzed using least squares Mendelian and parent-of-origin interval-mapping models. Lack-of-fit tests between models were used to characterize the QTL for mode of gene expressions. A total of 10 (32) QTL were detected at the 5% genome (chromosome)-wise level for the analyzed traits. Of the 42 QTL detected, 13 QTL were classified as Mendelian, 10 as paternal, 14 as maternal, and 5 as partial expressed QTL, respectively. Among the QTL detected at 5% genome-wise level, four QTL had Mendelian mode of inheritance on SSCs 5, 10, 12, and 13 for cooking loss, drip loss, crude lipid and crude protein, respectively; two QTL maternal inheritance for pH at 24-h and shear force on SSC11; three QTL paternal inheritance for CIE b and Hunter b on SSC9 and for cooking loss on SSC15; and one QTL partial expression for crude ash on SSC13, respectively. Most of the Mendelian QTL (9 of 13) had a dominant mode of gene action, suggesting potential utilization of heterosis for genetic improvement of meat quality within the cross population via marker-assisted selection.

• BMB Reports
• /
• 제43권2호
• /
• pp.115-121
• /
• 2010

A large data set of Hanwoo (Korean cattle) ESTs was analyzed to obtain differential gene expression results for the following three libraries: intramuscular fat, longissimus dorsi muscle and liver. To better understand the gene expression profiles, we identified differentially expressed genes (DEGs) via digital gene expression analysis. Hierarchical clustering of genes was performed according to their relative abundance within the six separate groups (Hanwoo fat versus non-Hanwoo fat, Hanwoo muscle versus non-Hanwoo muscle and Hanwoo liver versus non-Hanwoo liver), producing detailed patterns of gene expression. We determined the quantitative traits associated with the highly expressed genes. We also provide the first list of putative regulatory elements associated with differential tissue expression in Hanwoo cattle. In addition, we conducted evolutionary analysis that suggests a subset of genes accelerated in the bovine lineage are strongly correlated with their expression in Hanwoo muscle.

• 생명과학회지
• /
• 제19권9호
• /
• pp.1239-1244
• /
• 2009

본 연구는 제주도에서 자생하는 새우난초 3개체, 금새우난초 3개체 그리고 변이종 14개체를 포함하여 총 20개체를 화색에 따라 분류하고 유전자지도를 작성하여 QTL분석을 하였다. 화색은 새우난초가 어두운 자색으로 CIE Lab값이 $40{\sim}50$ 정도였으며, 금새우난초는 황색으로 $110{\sim}130$ 정도였고, 변이종 개체들은 새우난초와 유사하거나 다소 높았다. PCR 결과 얻은 polymorphism이 인정되는 154개 marker에 대한 분리비 적합도 검정에서 51개 marker에서 5% 수준의 유의성이 인정되었으며, 유의성이 인정된 51개 marker 중에서 새우난초 type은 37개, 금새우난초 type은 14개 였다. Polymorphism이 인정된 154개 marker에 대하여 MAPL program을 이용하여 이들 marker 상호간의 연관관계를 분석한 결과는 16개의 연관군과 1개의 독립군으로 구분되었으며, 이들 연관군에 대한 분자연관지도는 전체 group의 크기가 220.4 cM (centi Morgan)이고, marker간의 평균거리는 3.3 cM이었다. 양적 형질에 대한 분자연관지도상의 QTL 분석 결과, LOD 3.0 이상인 화색과 설판색의 QTL은 각각 3개와 1개였다. 이상에서 얻어진 자료는 새우난초 속의 화색 연구에 도움이 될 것으로 사료된다.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.116-116
• /
• 2017

Low-temperature is one of the environmental stress factors that affect plant growth and development and consequently limit crop productivity. The control of seed germination under low-temperature is organized by many genes which are called quantitative trait loci (QTLs). High germination rate for low-temperature is an important factor of growing rice. Previously, we identified a major QTL controlling low-temperature germinability in rice using 96 introgression lines (ILs) derived from a cross between Oryza rufipogon (Rufi) and the Korean japonica cultivar, 'Hwaseongbyeo (HS)'. A $BC_3F_7$ line (TR5) showed better low-temperature germinability than its recurrent parent. TR5 was crossed with HS to develop a segregating F2:3 populations for the target QTL. Six SSR markers polymorphic between HS and Rufi were used to screen and fine map the qLTG1. The qLTG1 on chromosome 1, which accounted for 55.5% of the total phenotypic variation, confirmed that Rufi allele enhanced the low-temperature germinability. Intervals between markers CRM16 and CRM15, four candidate genes were identified. The identified candidate genes, which are encoded by a protein of unknown function, showed their direct involvement on seed germination at low-temperature. To identify genes targeted by qLTG1, we investigated the expression profiles of these candidate genes and germination behavior of qLTG1 under different stress conditions and compared to HS, Rufi, and TR5 at $13{\pm}2^{\circ}C$ for 3 days after incubation. Furthermore, transgenic rice plants will also be developed to conduct a detailed investigation on low-temperature germinability. Hence, the QTL for low-temperature germinability would be useful in rice breeding programs especially in the development of lines possessing low-temperature germinability.

• 한국수정란이식학회지
• /
• 제19권3호
• /
• pp.291-299
• /
• 2004

요크셔종과 버크셔종 교배 실험 집단을 활용하여 양적형질 유전자좌 (QTL)의 발현 특성 관련 유전 양식을 조사하였다. 총 512두의 F$_2$ 자손이 F$_1$간의 65교배 조합으로부터 생산되었으며 표현형 조사 기록은 일당증제량(ADG), 평균 등지방 두께(ABF), 10번째 등뼈 부위 등지방 두께(TRF) 및 등심단면적(LEA), 최후 척추부위 등지방 두께 (LRF)였다. 125종의 유전자 표지 (microsatellite)에 대한 3세대 개체별 유전자형이 분석되었으며 이들 정보를 통하여 최소자승 회귀 모형을 이용한 interval mapping 방법을 적용하였다. QTL의 유전양식 여부 검정에 대한 절차를 도식화하기 위해 귀무가설인 통상의 벤델리안 모형에 근거를 두고 수행하였다. 경험적 다중 검정 통계량에 대한 임계치는 단일 개개의 염색체 수준과 게놈 전반에 걸친 실험수준으로 유도하였으며, permutation에 의해 유도된 임계치의 유효성을 검증하기 위해 본 연구에 활용된 실험축 집단 구조와 유사한 simulation 집단 구조에 의해 산출된 결과들과 비교하여 유효성이 인정되었다. 본 연구에 활용된 실험축 집단구조와 Genome 전반에 걸친 QTL imprinting 여부를 조사한 결과 13종의 QTL 에 대한 imprinting이 확인되었으며 이들 중 9종의 QTL 유전 양식은 부계로부터 전달된 자손에게만 발현되는 것으로 추론되었다.

• Journal of Plant Biotechnology
• /
• 제44권2호
• /
• pp.142-148
• /
• 2017

Drought stress is one of the important factors that restrict the expansion of Hevea brasiliensis cultivation to non-traditional regions experiencing extreme weather conditions. Plants respond to drought stress by triggering expression of several drought responsive genes including transcription factors which in turn trigger expression of various downstream signalling pathways and adaptive networks. Expression of such drought responsive genes may revert back to their original level upon re-watering. However, no reports are available on such phenomenon in Hevea and hence, this study was initiated. For this purpose, NAC transcription factor (NAC tf) was chosen as candidate gene. Its expression levels were monitored under intermittent drought as well as irrigated conditions in two clones (RRII 105 and RRIM 600) of H. brasiliensis with contrasting tolerance level. Copy number of NAC tf was found similar in both the clones. Expression of NAC tf was found highly up-regulated in RRIM 600 (a relatively drought tolerant clone) than in RRII 105 (a relatively drought susceptible clone) throughout the drought incidences which upon re-watering, reached back to its original levels in both the clones. The study indicated the existence of an association between expression of NAC tf and drought tolerance trait exhibited by the tolerant clone RRIM 600. The study also proves the influence of drought and re-watering on the leaf photosynthesis and expression of NAC tf in H. brasiliensis.

• Molecules and Cells
• /
• 제42권4호
• /
• pp.333-344
• /
• 2019

Various genetic and environmental factors are known to be associated with chronic obstructive pulmonary disease (COPD). We identified COPD-related differentially expressed genes (DEGs) using 189 samples accompanying either adenocarcinoma (AC) or squamous cell carcinoma (SC), comprising 91 normal and 98 COPD samples. DEGs were obtained from the intersection of two DEG sets separately identified for AC and SC to exclude the influence of different cancer backgrounds co-occurring with COPD. We also measured patient samples named group 'I', which were unable to be determined as normal or COPD based on alterations in gene expression. The Gene Ontology (GO) analysis revealed significant alterations in the expression of genes categorized with the 'cell adhesion', 'inflammatory response', and 'mitochondrial functions', i.e., well-known functions related to COPD, in samples from patients with COPD. Multi-omics data were subsequently integrated to decipher the upstream regulatory changes linked to the gene expression alterations in COPD. COPD-associated expression quantitative trait loci (eQTLs) were located at the upstream regulatory regions of 96 DEGs. Additionally, 45 previously identified COPD-related miRNAs were predicted to target 66 of the DEGs. The eQTLs and miRNAs might affect the expression of 'respiratory electron transport chain' genes and 'cell proliferation' genes, respectively, while both eQTLs and miRNAs might affect the expression of 'apoptosis' genes. We think that our present study will contribute to our understanding of the molecular etiology of COPD accompanying lung cancer.