title: Genetic regulation of differentially methylated genes in visceral adipose tissue of severely obese men discordant for the metabolic syndrome.
abstract: A genetic influence on methylation levels has been reported and methylation quantitative trait loci (meQTL) have been identified in various tissues. The contribution of genetic and epigenetic factors in the development of the metabolic syndrome (MetS) has also been noted. To pinpoint candidate genes for testing the association of SNPs with MetS and its components, we aimed to evaluate the contribution of genetic variations to differentially methylated CpG sites in severely obese men discordant for MetS. A genome-wide differential methylation analysis was conducted in visceral adipose tissue (VAT) of 31 severely obese men discordant for MetS (16 with and 15 without MetS) and identified ∼17,800 variable CpG sites. The genome-wide association study conducted to identify the SNPs (meQTL) associated with methylation levels at variable CpG sites revealed 2292 significant associations (P < 2.22 × 10-11) involving 2182 unique meQTLs regulating the methylation levels of 174 variable CpG sites. Two meQTLs disrupting CpG sites located within the collagen-encoding COL11A2 gene were tested for associations with MetS and its components in a cohort of 3021 obese individuals. Rare alleles of these meQTLs showed association with plasma fasting glucose levels. Further analysis conducted on these meQTL suggested a biological impact mediated through the disruption of transcription factor (TF)-binding sites based on the prediction of TF-binding affinities. The current study identified meQTL in the VAT of severely obese men and revealed associations of two COL11A2 meQTL with fasting glucose levels.
authors.affiliation: Institute of Nutrition and Functional Foods (INAF), Québec, Canada; School of Nutrition, Laval University, Québec, Canada.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Guénard
authors.affiliation: School of Nutrition, Laval University, Québec, Canada; Québec Heart and Lung Institute, Québec, Canada.
authors.forename: André
authors.initials: A
authors.lastname: Tchernof
authors.affiliation: Québec Heart and Lung Institute, Québec, Canada; Department of Medicine, Laval University, Québec, Canada.
authors.forename: Yves
authors.initials: Y
authors.lastname: Deshaies
authors.affiliation: Department of Surgery, Laval University, Québec, Canada.
authors.forename: Simon
authors.initials: S
authors.lastname: Biron
authors.affiliation: Department of Surgery, Laval University, Québec, Canada.
authors.forename: Odette
authors.initials: O
authors.lastname: Lescelleur
authors.affiliation: Department of Surgery, Laval University, Québec, Canada.
authors.forename: Laurent
authors.initials: L
authors.lastname: Biertho
authors.affiliation: Department of Surgery, Laval University, Québec, Canada.
authors.forename: Simon
authors.initials: S
authors.lastname: Marceau
authors.affiliation: Institute of Nutrition and Functional Foods (INAF), Québec, Canada; Department of Kinesiology, Laval University, Québec, Canada.
authors.forename: Louis
authors.initials: L
authors.lastname: Pérusse
authors.affiliation: Institute of Nutrition and Functional Foods (INAF), Québec, Canada; School of Nutrition, Laval University, Québec, Canada. Electronic address: marie-claude.vohl@fsaa.ulaval.ca.
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Vohl
mesh_terms: D000328:Adult; D018899:CpG Islands; D019175:DNA Methylation; D057890:Epigenomics; D005786:Gene Expression Regulation; D055106:Genome-Wide Association Study; D006801:Humans; D050152:Intra-Abdominal Fat / Q000473:pathology / Q000502:physiology*; D008297:Male; D024821:Metabolic Syndrome / Q000235:genetics*; D008875:Middle Aged; D009765:Obesity / Q000235:genetics* / Q000473:pathology; D056128:Obesity, Abdominal / Q000235:genetics / Q000473:pathology; D020641:Polymorphism, Single Nucleotide