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<p>The Human Liver Cohort (HLC) study aimed to characterize the genetic architecture of gene expression in human liver using genotyping, gene expression profiling, and enzyme activity measurements of Cytochrom P450. The HLC was assembled from a total of 780 liver samples screened. These liver samples were acquired from caucasian individuals from three independant tissue collection centers. DNA samples were genotyped on the Affymetrix 500K SNP and Illumina 650Y SNP genotyping arrays representing a total of 782,476 unique single nucleotide polymorphisms (SNPs). Only the genotype data from those samples which were collected postmortem are accessible in dbGap. These 228 samples represent a subset of the 427 samples included in the Human Liver Cohort Publication (Schadt, Molony et al. 2008). RNA samples were profiled on a custom Agilent 44,000 feature microarray composed of 39,280 oligonucleotide probes targeting transcripts representing 34,266 known and predicted genes, including high-confidence, noncoding RNA sequences. Each of the liver samples was processed into cytosol and microsomes using a standard differential centrifugation method. The activities of nine P450 enzymes (CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4) in isolated microsomes from 398 HLC liver samples were measured in the microsome preparations using probe substrate metabolism assays expressed as nmol/min/mg protein. Each was measured with a single substrate except for the CYP3A4 activity that was measured using two substrates, midazolam and testosterone.</p>
<p>To uncover the genetic determinants affecting expression in a metabolically active tissue relevant to the study of obesity, diabetes, atherosclerosis, and other common human diseases, we profiled 427 human liver samples on a comprehensive gene expression microarray targeting greater than 40,000 transcripts and genotyped DNA from each of these samples at greater than 1,000,000 SNPs. The relatively large sample size of this study and the large number of SNPs genotyped provided the means to assess the relationship between genetic variants and gene expression and it provided this look for the first time in a non-blood derived, metabolically active tissue. A comprehensive analysis of the liver gene expression traits revealed that thousands of these traits are under the control of well defined genetic loci, with many of the genes having already been implicated in a number of human diseases.</p>
<p>Clincal data was requested, but not provided by submitter. Keywords: eQTL</p>
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