title: Gene-carbohydrate and gene-fiber interactions and type 2 diabetes in diverse populations from the National Health and Nutrition Examination Surveys (NHANES) as part of the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study.
abstract: BACKGROUND
  Both environmental and genetic factors impact type 2 diabetes (T2D). To identify such modifiers, we genotyped 15 T2D-associated variants from genome-wide association studies (GWAS) in 6,414 non-Hispanic whites, 3,073 non-Hispanic blacks, and 3,633 Mexican American participants from the National Health and Nutrition Examination Surveys (NHANES) and evaluated interactions between these variants and carbohydrate intake and fiber intake.
  
  
  RESULTS
  We calculated a genetic risk score (GRS) with the 15 SNPs. The odds ratio for T2D with each GRS point was 1.10 (95% CI: 1.05-1.14) for non-Hispanic whites, 1.07 (95% CI: 1.02-1.13) for non-Hispanic blacks, and 1.11 (95% CI: 1.06-1.17) for Mexican Americans. We identified two gene-carbohydrate interactions (P < 0.05) in non-Hispanic whites (with CDKAL1 rs471253 and FTO rs8050136), two in non-Hispanic blacks (with IGFBP2 rs4402960 and THADA rs7578597), and two in Mexican Americans (with NOTCH2 rs1092398 and TSPAN8-LGRS rs7961581). We found three gene-fiber interactions in non-Hispanic whites (with ADAMT59 rs4607103, CDKN2A/2B rs1801282, and FTO rs8050136), two in non-Hispanic blacks (with ADAMT59 rs4607103 and THADA rs7578597), and two in Mexican Americans (with THADA rs7578597 and TSPAN8-LGRS rs796158) at the P < 0.05 level. Interactions between the GRS and nutrients failed to reach significance in all the racial/ethnic groups.
  
  
  CONCLUSIONS
  Our results suggest that dietary carbohydrates and fiber may modify T2D-associated variants, highlighting the importance of dietary nutrients in predicting T2D risk.
authors.affiliation: Vanderbilt Epidemiology Center, Department of Medicine, Vanderbilt University Medical Center, 2525 West End Avenue, Suite 600, Nashville, TN 37203-1738, USA. raquel.villegas@vanderbilt.edu.
authors.forename: Raquel
authors.initials: R
authors.lastname: Villegas
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Goodloe
authors.forename: Bob E
authors.initials: BE
authors.lastname: McClellan
authors.forename: Jonathan
authors.initials: J
authors.lastname: Boston
authors.forename: Dana C
authors.initials: DC
authors.lastname: Crawford
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044383:Black People / Q000235:genetics; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D004040:Dietary Carbohydrates; D004043:Dietary Fiber; D005260:Female; D059647:Gene-Environment Interaction; D055106:Genome-Wide Association Study; D005838:Genotype; D006801:Humans; D008297:Male; D017058:Mexican Americans / Q000235:genetics; D008875:Middle Aged; D009749:Nutrition Surveys; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D044465:White People / Q000235:genetics; D055815:Young Adult
chemical_list: D004040:Dietary Carbohydrates; D004043:Dietary Fiber