title: RGS6 variants are associated with dietary fat intake in Hispanics: the IRAS Family Study.
abstract: Recently, a genome-wide association scan was completed in the IRAS (Insulin Resistance Atherosclerosis Study) Family Study (IRASFS) Hispanic-American cohort. Multiple single-nucleotide polymorphisms (SNPs) in the G-protein signaling 6 (RGS6) gene were found to be associated with adiposity phenotypes. RGS6 has shown downstream antagonistic interplay with opioid receptors, targets of fatty/sugary food agonists. The possibility that RGS6 promotes tolerance and tachyphylaxis among the opioid receptor is a plausible pathway for overconsuming fat/sugar-laden food. Therefore, we hypothesized that RGS6 variants are associated with intake of fatty/sugary foods. In 932 Hispanics from San Antonio and San Luis Valley, CO, the following dietary intake variables were assessed using the Block Brief 2000 food frequency questionnaire: total calories, total fat, % calories from fat, % calories from saturated fat, protein, % calories from protein, carbohydrates, % calories from carbohydrates, and daily frequency of servings of fats/oils/sweets. We tested for association between 23 SNPs in RGS6 and dietary intake using a variance components measured genotype approach. All models were adjusted for gender, recruitment site, admixture, BMI, and age. Using an additive genetic model, rs1402064 was associated with higher intake of fats/oils/sweets, total calories, total fat and saturated fat (P = 0.0007, 0.026, 0.023, and 0.024). SNPs rs847330 and rs847354 were associated with higher intake of fats/oils/sweets (P = 0.002 and 0.018), total fat (P = 0.040 and 0.048) and saturated fat (P = 0.044 and 0.041). Finally, rs769148 was associated with higher intake of fats/oils/sweets (P = 0.002). RGS6 is a new candidate gene for adiposity traits that may be associated with a behavioral tendency toward fat-laden food intake.
authors.affiliation: Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver, Aurora, Colorado, USA.
authors.forename: Scott P
authors.initials: SP
authors.lastname: Sibbel
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Talbert
authors.forename: Donald W
authors.initials: DW
authors.lastname: Bowden
authors.forename: Steve M
authors.initials: SM
authors.lastname: Haffner
authors.forename: Kent D
authors.initials: KD
authors.lastname: Taylor
authors.forename: Yii-Der I
authors.initials: YD
authors.lastname: Chen
authors.forename: Lynne E
authors.initials: LE
authors.lastname: Wagenknecht
authors.forename: Carl D
authors.initials: CD
authors.lastname: Langefeld
authors.forename: Jill M
authors.initials: JM
authors.lastname: Norris
mesh_terms: D050154:Adiposity; D000328:Adult; D015992:Body Mass Index; D015331:Cohort Studies; D003120:Colorado; D004032:Diet / Q000208:ethnology; D004041:Dietary Fats / Q000008:administration & dosage*; D019422:Dietary Sucrose / Q000008:administration & dosage*; D005192:Family Health; D005260:Female; D005518:Food Preferences / Q000208:ethnology*; D056726:Genetic Association Studies; D055106:Genome-Wide Association Study; D006630:Hispanic or Latino / Q000235:genetics* / Q000523:psychology; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000235:genetics; D020710:RGS Proteins / Q000235:genetics*; D013781:Texas
chemical_list: D004041:Dietary Fats; D019422:Dietary Sucrose; D020710:RGS Proteins; C400194:RGS6 protein, human