Project description:gnp07_rilkit - rilkit-eqtl analysis (random pair design). To provide quantitative geneticists studying natural variation in our RIL populations with information and resources necessary to speed up QTL cloning and candidate genes identification. This articulates around the creation of two major resources and their integration into databases to make the information accessible to users: A. Whole transcriptome survey, B. Production of complementary material. Comparison of 164 Cvi/Col(8RV) Recombinant Inbred Lines (RILs) and 164 Bur/Col (20RV) RILs.
Project description:gnp07_rilkit - rilkit-eqtl analysis (random pair design). To provide quantitative geneticists studying natural variation in our RIL populations with information and resources necessary to speed up QTL cloning and candidate genes identification. This articulates around the creation of two major resources and their integration into databases to make the information accessible to users: A. Whole transcriptome survey, B. Production of complementary material. Comparison of 164 Cvi/Col(8RV) Recombinant Inbred Lines (RILs) and 164 Bur/Col (20RV) RILs. 162 dye-swaps. Genotype and ecotype comparison.
Project description:gnp3_tri33-arabidoseed - eqtl analysis (random pair design) - WP3 : Biodiversity of seed traits : state of the art - Comparison of the developping seed transcriptome in 160 Bay0/Sha Recombinant Inbred Lines (RILs) at 10 days after pollinisation. Keywords: genotype and ecotype comparison
Project description:Expression level polymorphisms (ELPs) often result in cis-acting expression quantitative trait loci (cis-eQTL), which are important QTL and association mapping tools and account significantly for phenotypic variability. Generally, it is assumed that such stably heritable ELP represent regulatory element polymorphisms in the respective genes. However, comprehensive genome-wide analyses linking expression level, regulatory sequence and gene structure variation are missing, preventing definite verification of this assumption. Here we analyzed heritability of ELP observed between Arabidopsis thaliana accessions Eil-0 and Lc-0 by comparing genotyped recombinant inbred lines (RIL) to their parents in microarray analyses. Keywords: expression level polymorphism, Arabidopsis thaliana accessions, recombinant inbred lines
Project description:Expression level polymorphisms (ELPs) often result in cis-acting expression quantitative trait loci (cis-eQTL), which are important QTL and association mapping tools and account significantly for phenotypic variability. Generally, it is assumed that such stably heritable ELP represent regulatory element polymorphisms in the respective genes. However, comprehensive genome-wide analyses linking expression level, regulatory sequence and gene structure variation are missing, preventing definite verification of this assumption. Here we analyzed heritability of ELP observed between Arabidopsis thaliana accessions Eil-0 and Lc-0 by comparing genotyped recombinant inbred lines (RIL) to their parents in microarray analyses. Keywords: expression level polymorphism, Arabidopsis thaliana accessions, recombinant inbred lines In order to analyze expression level polymorphisms between the accessions Eil-0 and Lc-0, three independently grown seedling pools were analyzed by two color co-hybridization of the labeled cDNAs in dyeswap experiments, giving a total of six slides. For the analysis of gene expression in seedlings of 7 different RILs, each RIL sample was co-hybridized with each parent (Eil-0 and Lc-0) in a dyeswap, resulting in two slides per parent vs. RIL comparison. The total number of slides in this study was 34.
Project description:affy_zeawall_ril_maize - Four major QTL explaining lignin content and cell wall degradability variation have been identified in the F288 x F271 RIL progeny (Roussel et al., 2002, Maydica 47: 9-20). Gene expression has been considered as a way in identification of candidate gene underlying QTL. Five lines chosen for their allelic pattern at four main QTL were considered for expression studies, two lines with all four favorable alleles (RIL99, RIL54), two lines with the unfavorable allele at bin 6.06 QTL position (RIL39 , RIL71), and one line with the unfavorable allele at bin 9.02 QTL position (RIL118). Expression study will be investigated in ear internode at two stages emerging tassel and early silking stages with two replicates. Plants were cropped at INRA Lusignan (Vienne, France) in 2009 in a bloc design with two four-row replicates. Below-ear internodes of five representative RIL plants of one row in each replicate were harvested at the two stages and pooled. Keywords: genotype comparison, time course
Project description:gnp3_tri33-arabidoseed - eqtl analysis (random pair design) - WP3 : Biodiversity of seed traits : state of the art - Comparison of the developping seed transcriptome in 160 Bay0/Sha Recombinant Inbred Lines (RILs) at 10 days after pollinisation. Keywords: genotype and ecotype comparison 80 dye-swap - CATMA arrays
Project description:Gene expression is regulated by genetic variants and DNA methylation with evidence from molecular biology studies, as well as expression QTL (eQTL) mapping and methylation QTL (mQTL) mapping. In this study, we explored the interaction between genetic variants and DNA methylation for its influence on gene expression. We analyzed a postmortem brain data and identified 2,768 SNP-methylation interaction (SMI) that can survive Bonferroni correction for the number of tests in cis- region of each gene. Seven SNP-methylation pairs were significant after Bonferroni correction for all the tests, including number of gene expression traits, we performed in this study. Only a small proportion of the SMI had evidence from the exact same SNP-transcript pair in eQTL mapping or SNP-methylation pair in mQTL mapping. This suggested that the interaction analysis could uncover novel regulatory relationships, which would be missed by eQTL or mQTL analyses. Since methylation per se is regulated by both genetic and environmental factors, analysis indicates that the SMI detected in this study may involve both genetic and environmental regulation. A total of 155 postmortem cerebellum brains were used in this study, including 47 bipolar disorder, 46 schizophrenia, 15 depression patients and 47 normal controls. All were of European Ancestry. We also designed 13 random replicates in our experiment. Illumina Infinium HumanMethylation27 BeadChip was used for DNA methylation profiling. The assay was performed at the Genomics Core Facility at Northwestern University.
Project description:We used microarrays and a previously established linkage map to localize the genetic determinants of brain gene expression for a backcross family of lake whitefish species pairs (Coregonus sp.). Our goals were to elucidate the genomic distribution and sex-specificity of brain expression QTL (eQTL) and to determine the extent to which genes controlling transcriptional variation may underlie adaptive divergence in the recently evolved dwarf (limnetic) and normal (benthic) whitefish. We observed a sex-bias in transcriptional genetic architecture, with more eQTL observed in males, as well as divergence in genome location of eQTL between sexes. Hotspots of nonrandom aggregations of up to 32 eQTL in one location were observed. We identified candidate genes for species pair divergence involved with energetic metabolism, protein synthesis, and neural development based on co-localization of eQTL for these genes with eight previously identified adaptive phenotypic QTL and four previously identified outlier loci from a genome scan in natural populations. 88% of eQTL-phenotypic QTL co-localization involved growth rate and condition factor QTL, two traits central to adaptive divergence between whitefish species pairs. Hotspots co-localized with phenotypic QTL in several cases, revealing possible locations where master regulatory genes, such as a zinc finger protein in one case, control gene expression directly related to adaptive phenotypic divergence. We observed little evidence of co-localization of brain eQTL with behavioral QTL, which provides insight on the genes identified by behavioral QTL studies. These results extend to the transcriptome level previous work illustrating that selection has shaped recent parallel divergence between dwarf and normal lake whitefish species pairs and that metabolic, more than morphological differences appear to play a key role in this divergence. Keywords: eQTL mapping, gene expression, linkage mapping, adaptive radiation, Coregonus, microarrays
Project description:The aim of this study was to identify candidate genes responsible for grain number per panicle between a pair of rice varieties (Pusa 1266 and Pusa Basmati 1) by combining QTL analysis with expression analysis. Microarray analysis of RNA extracted from the panicle primordia showed 2741 differentially expressed genes. The differentially expressed genes were shortened to 18 on the basis of their occurance in the QTL region (responsible for grain number regulation) detected in RIL population derived from Pusa 1266 and Pusa Basmati 1.