Gene expression data from peripheral blood leukocytes of Amish and Hutterite schoolchildren
Ontology highlight
ABSTRACT: The Amish and Hutterites are U.S. farming populations with remarkably similar lifestyles. However, the Amish follow traditional farming practices, while the Hutterites employ modern farming techniques, and also show striking differences in asthma prevalence. Little is known about immune responses underlying these differences. To address this, we obtained genome-wide gene expression data in peripheral blood leukocytes from Amish and Hutterite schoolchildren. The study includes data from whole blood samples from age- and sex-matched Amish and Hutterite schoolchildren. Written consent was obtained from the parents and written assent was obtained from the children. One mL of whole blood was drawn into a TruCulture tube containing media alone, and incubated upright on a dry heat block at 37°C for 30 hours. Cells were isolated and total RNA was extracted using Qiagen AllPrep DNA/RNA Mini Kits. RNA concentration was assayed with a Nanodrop ND-100 Sepectrophotometer; RNA quality was assessed with an Agilent 2100 Bioanalyzer. Samples underwent cDNA synthesis and were then hybridized on the Illumina HumanHT-12 v4 Expression BeadChip arrays at the Functional Genomics Core at the University of Chicago.
Project description:Pregnancy loss is the most common complication of human pregnancy. Recurrent early pregnancy loss (REPL) has multiple etiologies, including endometrial dysregulation leading to “suboptimal” implantation. Although the implantation process is tightly regulated in Eutherian (placental) mammals, the molecular factors contributing to dysregulated endometrial gene expression patterns in women with REPL are largely unknown. We hypothesized that genes that gained novel expression in the endometria of mammals that evolved in the Eutherian stemlineage, coincident with the evolution of pregnancy, are likely essential for establishment and maintenance of normal pregnancy and are, therefore, good candidates for genes whose expression may be dysregulated in disorders such as REPL. To test this hypothesis, we took an evolutionary forward genomics approach to characterize gene expression profiles of midsecretory endometria from women with REPL associated with abnormal endometria based either on histology or molecular expression of cyclin E. We identified 58 genes that were differentially expressed (P<0.001) between women with out-of-phase histological dating vs normal histology, and 81 genes that were differentially expressed (P<0.001) between women with abnormally elevated cyclin E levels vs normal cyclin E. Remarkably, genes that were recruited into endometrial expression during the evolution of pregnancy in Eutherian mammals were significantly enriched for dysregulated genes (P=0.002 for histology, P=0.021 for cyclin E), as well as for immune and signaling pathways with essential roles in endometrial biology. Thus, our novel evolutionary-based forward genomics approach identified genes whose dysregulation during the mid-secretory phase likely contributes to the molecular etiologies of recurrent early pregnancy loss. Total RNA obtained from mid luteal phase endometrium (two replicates per biopsy) from women with recurrent early pregnancy loss (REPL). Endometrial gene expression levels were compared 1) between women with out-of-phase (n=10) and normal histological dating (n=22), 2) between women with abnormally elevated (n=9) and normal (n=23) cyclin E levels. For 5 additional women with abnormally high cyclin E levels, biopsy samples were collected before and after progesterone treatment to investigate the gene expression profiles in response to progesterone.
Project description:This study aimed to determine skeletal muscle DNA methylation changes in a cohort of volunteers with a range of insulin sensitivities following 8-weeks of supervised exercise training. We studied 13 sedentary participants (5M/8F, 34.6 ± 3.1 years) and performed euglycemic hyperinsulinemic clamps with vastus lateralis muscle biopsies and peak aerobic activity (VO2 peak) tests before and after training. We extracted DNA from the muscle biopsies and performed global methylation using Illumina's Methylation EPIC 850K BeadChip.
Project description:Background: The mechanisms of how genetic variants (SNPs) identified in genome-wide association studies act to influence body mass remain unknown for most of these SNPs, which continue to puzzle the scientific community. Recent evidence points to epigenetic and chromatin state of the genome to have an important role. Methods: 355 healthy young individuals were genotyped for 52 known obesity-associated SNPs and we obtained DNA methylation levels in their blood using the Illumina 450K BeadChip. Associations between alleles and methylation at proximal cytosine residues were tested using a linear model adjusted for age, sex, weight category and a proxy for blood cell type counts. For replication in other tissues, we used two open-access datasets (skin fibroblasts, n=62; four brain regions, n=121-133) and an additional dataset in subcutaneous and visceral fat (n=149). Results: We found that alleles at 28 of these obesity-associated SNPs associate with methylation levels at 107 proximal CpG sites. Out of 107 CpG sites, 38 are located in gene promoters, including genes strongly implicated in obesity (MIR148A, BDNF, PTPMT1, NR1H3, MGAT1, SCGB3A1, HOXC12, PMAIP1, PSIP1, RPS10-NUDT3, RPS10, SKOR1, MAP2K5, SIX5, AGRN, IMMP1L, ELP4, ITIH4, SEMA3G, POMC, ADCY3, SSPN, LGR4, TUFM, MIR4721, SULT1A1, SULT1A2, APOBR, CLN3, SPNS1,SH2B1, ATXN2L, and IL27). Interestingly, the associated SNPs are in known eQTLs for some of these genes. We also found that the 107 CpGs are enriched in enhancers in peripheral blood mononuclear cells. Finally, our results indicate that some of these associations are not be blood-specific as we successfully replicated four associations in skin fibroblasts. Conclusions: Our results strongly suggest that many obesity-associated SNPs are associated with proximal gene regulation, which was reflected by association of obesity risk allele genotypes with differential DNA methylation. This study highlights the importance of DNA methylation and other chromatin marks as a way to understand the molecular basis of genetic variants associated to human diseases and traits. Bisulphite converted DNA from 355 individuals aged 14-34 were hybridised to the Illumina Infinium 450k Human Methylation Beadchip.
Project description:Purpose Despite advances and significant improvement in survival, multiple myeloma (MM) remains incurable and nearly all patients relapse after treatment. Previous studies have shown a complex spectrum of diverse genetic alterations in almost all patients, but evolution of genomic rearrangements throughout myeloma life cycle has not been investigated. Patients and Methods We performed genomic analysis integrating copy number, allele specific copy number, allele ratio calculations, breakpoint sequencing and rearrangement PCR genotyping on matched diagnosis and relapse samples from 24 MM patients either treated with proteasome inhibitor (bortezomib)-based induction regimen or conventional chemotherapeutic agents. Results All relapse samples have a clear relationship to the diagnosis clone with significant increase of copy number abnormalities (CNAs). Despite a wide diversity of CNAs acquired at relapse, regulators of NF-kB activity were targeted in 25% of the patients. Relapse-associated lesions either appeared as new acquisition or were selected from minor subpopulations at diagnosis. In one third of the patients, we found loss of abnormities containing loss of heterozygosity (LOH) providing evidence that the relapse clone derived from an ancestral clone shared with the dominant diagnosis clone. Remarkably, re-emergence of ancestral clones was almost exclusively found in patients treated with bortezomib, attested to a remarkable adaptability of myeloma cells under targeted drug selection pressure. Conclusion These data suggest that genomic instability and clonal selection are the main forces that drive adaptive changes in MM under drug selection pressure, and they support the proposal to combine several anti-myeloma drugs upfront in order to obtain long-term remissions. [SNP genotyping] 24 myeloma patients at diagnosis and relapse examined with high resolution genome-wide chip
Project description:The Ashkenazi Jewish population has long been considered a genetic isolate and presumed to have the genetic signatures of founder effects and isolation. We genotyped a large cohort of Ashkenazi Jews and analyzed their genetic structure compared to other worldwide populations. We genotyped 471 normal control Ashkenazi Jewish individuals with the Affymetrix 6.0 array and analyzed their genetic structure relative to other Europe and worldwide populations. We measured heterozygosity, linkage disequilibrium, identity-by-descent and used extended haplotype tests of positive selection.
Project description:In this study 3 pooling experiments were performed. In each of the 3 cohorts, a 'case' and a 'control' blood pool was compared - the goal being to identify single nucleotide polymorphisms with significantly different estimated pooling allele frequencies between cases and controls. For cohort 1, 100 individuals with blue eye color were placed in one pool (the 'control' pool) and 100 individuals with brown eye color were placed in another pool ( the 'case' pool). In cohort 2, 131 individuals with age-related macular degeneration were placed in one pool, with 216 control individuals in another pool. In cohort 3, 100 individuals with pseudoexfoliation syndrome were placed in a case pool - in this case the cohort 2 control sample was used as 'controls'. The blue/brown pools were hybridized to Illumina HumanHap550 arrays. The cohort 2 and 3 pools were hybridized to Illumina 1M arrays. After processing, the raw data are summarized to give pooling allele frequency estimates for each pool. The abstract from the paper describing these data is as follows: Genome-wide association studies (GWAS) have now successfully identified important genetic variants associated with many human traits and diseases. The high cost of genotyping arrays in large datasets remains the major barrier to wider utilization of GWAS. We have developed a novel method in which whole blood from cases and controls respectively is pooled prior to DNA extraction for genotyping. We demonstrate proof of principle by clearly identifying the associated variants for eye color, age-related macular degeneration and pseudoexfoliation syndrome in cohorts not previously studied. Blood pooling has the potential to reduce GWAS cost by several orders of magnitude and dramatically shorten gene discovery time. This method has profound implications for translation of modern genetic approaches to a multitude of diseases and traits yet to be analysed by GWAS, and will enable developing nations to participate in GWAS. Pools were typed with Illumina arrays. Estimates of pooling allele frequency were obtained.
Project description:Comment on published article "Massive genomic rearrangement acquired in a single catastrophic event during cancer development." by Stephens, P.J., Greenman, C.D., Beiyuan, F., Yang, F., Bignell, G.R., Mudie, L.J., Pleasance, E.D., Lau, K.W., Beare, D., Stebbings, L.A., et al. (2011). Cell 144, 27-40. [PMID: 21215367] 10 myeloma patients examined with high resolution genome-wide chip SUPPLEMENTARY FILE: Copy number table.
Project description:Epstein-Barr virus (EBV) transformed lymphoblastoid cell lines (LCLs) are a widely used renewable resource for functional genomic studies in humans. The ability to accumulate multidimensional data pertaining to the same individual cell lines, from complete genomic sequences to detailed gene regulatory profiles, further enhances the utility of LCLs as a model system. However, the extent to which LCLs are a faithful model system is relatively unknown. We have previously shown that gene expression profiles of newly established LCLs maintain a strong individual component. Here, we extend our study to investigate the effect of freeze-thaw cycles on gene expression patterns in mature LCLs, especially in the context of inter-individual variation in gene regulation. We found a profound difference in the gene expression profiles of newly established and mature LCLs. Once newly established LCLs undergo a freeze-thaw cycle, the individual specific gene expression signatures become much less pronounced as the gene regulatory programs in LCLs from different individuals converge to a more uniform profile, which reflects a mature transformed B cell phenotype. As expected, previously identified eQTLs are enriched among the relatively few genes whose regulations in mature LCLs maintain marked individual signatures. We thus conclude that findings and insight drawn from gene regulatory studies in mature LCLs are generally not affected by artificial nature of the LCL model system and are likely to faithfully reflect regulatory interactions in primary tissues. However, our data indicate that many aspects of primary B cell biology cannot be observed and studied in mature LCL cultures. We obtained unpurified buffy coats (of a unit of blood) from six unrelated healthy individuals of Caucasian ethnicity (age range: 20-45). We isolated CD20+ B cells and established six independent cultures of LCLs between October 2009 and January 2010. From each of these samples, we obtained genome wide gene expression data using Illumina HumanHT-12 v3 Expression BeadChip arrays. We refer to data from these experiments as M-bM-^@M-^\cycle 0M-bM-^@M-^] to acknowledge the fact that the LCLs from this cycle were newly established and therefore not frozen/thawed. Between February 2011 and October 2012, we thawed each of these LCL cultures every 3 months and cultured them until obtaining ~10 million cells (February 2011=cycle 1, June 2011=cycle 2, October 2011=cycle 3, February 2012=cycle 4, June 2012=cycle 5, and October 2012=cycle 6). We used Illumina HumanHT-12 v4 Expression BeadChip arrays and obtained genome wide gene expression data on cycle 2, cycle 4 and cycle 6 LCLs. At each hybridization batch we included a subset of RNA samples that were also hybridized in a previous batch. This allowed us to effectively consider the batch effect on gene expression profiles. Our final dataset included genome wide gene expression data from 187 samples collected at 4 different time points.
Project description:Background: Trisomy 21 causes Down syndrome (DS), but the mechanisms by which the extra chromosome leads to deficient intellectual and immune function are not well understood. Results: Here, we profile CpG methylation in DS and control cerebral and cerebellar cortex of adults and cerebrum of fetuses. We purify neuronal and non-neuronal nuclei and T-lymphocytes and find biologically relevant genes with DS-specific methylation (DS-DM) in brain cells. Some genes show brain-specific DS-DM, while others show stronger DS-DM in T cells. Both 5-methyl-cytosine and 5-hydroxy-methyl-cytosine contribute to the DS-DM. Thirty percent of genes with DS-DM in adult brain cells also show DS-DM in fetal brains, indicating early onset of these epigenetic changes, and we find early maturation of methylation patterns in DS brain and lymphocytes. Some, but not all, of the DS-DM genes show differential expression. DS-DM preferentially affected CpGs in or near specific transcription factor binding sites, implicating a mechanism involving altered transcription factor binding. Methyl-seq of brain DNA from mouse models with sub-chromosomal duplications mimicking DS reveals partial but significant overlaps with human DS-DM and shows that multiple chromosome 21 genes contribute to the downstream epigenetic effects. Conclusions: These data point to novel biological mechanisms in DS and have general implications for trans effects of chromosomal duplications and aneuploidies on epigenetic patterning. Bisulfite converted DNA from 119 samples from Down syndrome patients and controls were hybridised to the Illumina Infinium 450k Human Methylation Beadchip. In addition, we re-analyzed 6 Down syndrome and 6 control cerebellum DNA samples on the 450K BeadChips using an adaptation of the Illumina probe preparation protocol (TrueMethyl kit; Cambridge Epigenetics, CEGX), in which parallel analyses of bisulfite and oxidative bisulfite DNA for each sample allows assessment of the relative contributions of 5mC and 5hmC to net methylation.