title: Association of genetic variations and gene expression in a family-based study.
abstract: BACKGROUND
  Expression quantitative trait locus (eQTL) maps are considered a valuable resource in studying complex diseases. The availability of gene expression data from the Genetic Analysis Workshop 19 (GAW19) provides a great opportunity to investigate the association of gene expression with genetic variants in blood.
  
  
  METHODS
  A total of 267 samples with gene expression and whole genome sequencing data were employed in this study. We used linear mixed models with genetic random effects along with a permutation procedure to create an eQTL map. The eQTL map was further tested in terms of functional implication, including the enrichment in disease-related variants and in regulatory regions.
  
  
  RESULTS
  We identified 22,869 significant eQTLs from the GAW19 data set. These eQTLs were highly enriched with genetic loci associated with blood pressure and DNase hypersensitive regions. In addition, the majority of genes associated with eQTLs showed moderate to high heritability (h2> 0.4).
  
  
  CONCLUSIONS
  We successfully created an eQTL map from the GAW19 data set. Our study indicated that the eQTLs were enriched within regulatory regions, and tended to have relatively high heritability.
authors.affiliation: National Heart Lung and Blood Institute's Framingham Heart Study, 73 Mt. Wayte Avenue, Suite 2, Framingham, MA 01702 USA.
authors.forename: Achilleas N
authors.initials: AN
authors.lastname: Pitsillides
authors.affiliation: Department of Biostatistics, Boston University School of Public Health, 677 Huntington Avenue, Boston, MA 02115 USA.
authors.forename: Seung-Hoan
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Program in Bioinformatics, Boston University, Boston, MA 02215 USA.
authors.forename: John D
authors.initials: JD
authors.lastname: Hogan
authors.affiliation: Department of Biostatistics, Boston University School of Public Health, 677 Huntington Avenue, Boston, MA 02115 USA.
authors.forename: Jaeyoung
authors.initials: J
authors.lastname: Hong
authors.affiliation: National Heart Lung and Blood Institute's Framingham Heart Study, 73 Mt. Wayte Avenue, Suite 2, Framingham, MA 01702 USA ; Department of Medicine, Boston University School of Medicine, 72 East Concord St, Boston, MA 02118 USA.
authors.forename: Honghuang
authors.initials: H
authors.lastname: Lin