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- Franks, Paul, et al.
(author)
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Common variation in PPARGC1A/B and progression to diabetes or change in metabolic traits following preventive interventions: the Diabetes Prevention Program.
- 2013
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In: Diabetologia. - : Springer Science and Business Media LLC. - 1432-0428 .- 0012-186X.
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Journal article (peer-reviewed)abstract
- AIMS/HYPOTHESIS: PPARGC1A and PPARGC1B encode transcriptional coactivators that regulate numerous type 2 diabetes-related metabolic processes. Common genetic variation across PPARGC1A/B was characterised by genotyping tagging variants. We then tested associations of these variants with diabetes incidence or change in quantifiable metabolic traits directly or via interactions (with metformin treatment or intensive lifestyle modification) in the Diabetes Prevention Program (DPP), a randomised controlled trial in persons at high risk of type 2 diabetes. METHODS: We used Tagger software to select 75 PPARGC1A and 94 PPARGC1B tag single nucleotide polymorphisms (SNPs) for analysis. These SNPs were tested for association with diabetes incidence using Cox proportional hazards regression models, and a range of relevant metabolic quantifiable traits, using generalised linear models. RESULTS: Eight PPARGC1A variants were nominally (p < 0.05) associated with diabetes incidence, of which one (rs3736265/Thr612Met) was associated with diabetes in the DPP (HR 1.31, 95% CI 1.05, 1.63 per copy of the 612Met allele) and in the DIAGRAM database (OR 1.11, 95% CI 1.01, 1.21). Consistent with earlier reports, the Gly482Ser (rs8192678) variant showed nominally significant effects on 1 year accumulation of adiposity and worsening insulin resistance (both p < 0.05). A third PPARGC1A variant (rs2970852) modified the effects of metformin on triacylglycerol levels (p interaction = 0.04; p = 0.0001 for association of SNP with triacylglycerol concentrations in metformin-treated participants). A number of other PPARGC1A/B variants were nominally directly associated with diabetes incidence or modified treatment effects on diabetes incidence. CONCLUSIONS/INTERPRETATION: These findings provide some novel and confirmatory insights into the roles of PPARGC1A/B variation in type 2 diabetes and related metabolic traits. TRIAL REGISTRATION: ClinicalTrials.gov NCT00004992.
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- Mather, K J, et al.
(author)
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Common variants in genes encoding adiponectin (ADIPOQ) and its receptors (ADIPOR1/2), adiponectin concentrations, and diabetes incidence in the Diabetes Prevention Program.
- 2012
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In: Diabetic Medicine: A journal of the British Diabetic Association. - : Wiley. - 1464-5491.
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Journal article (peer-reviewed)abstract
- Aims Baseline adiponectin concentrations predict incident Type 2 diabetes mellitus in the Diabetes Prevention Program. We tested the hypothesis that common variants in the genes encoding adiponectin (ADIPOQ) and its receptors (ADIPOR1, ADIPOR2) would associate with circulating adiponectin concentrations and/or with diabetes incidence in the Diabetes Prevention Program population. Methods Seventy-seven tagging single-nucleotide polymorphisms (SNPs) in ADIPOQ (24), ADIPOR1 (22) and ADIPOR2 (31) were genotyped. Associations of SNPs with baseline adiponectin concentrations were evaluated using linear modelling. Associations of SNPs with diabetes incidence were evaluated using Cox proportional hazards modelling. Results Thirteen of 24 ADIPOQ SNPs were significantly associated with baseline adiponectin concentrations. Multivariable analysis including these 13 SNPs revealed strong independent contributions from rs17366568, rs1648707, rs17373414 and rs1403696 with adiponectin concentrations. However, no ADIPOQ SNPs were directly associated with diabetes incidence. Two ADIPOR1 SNPs (rs1342387 and rs12733285) were associated with ∼18% increased diabetes incidence for carriers of the minor allele without differences across treatment groups, and without any relationship with adiponectin concentrations. Conclusions ADIPOQ SNPs are significantly associated with adiponectin concentrations in the Diabetes Prevention Program cohort. This observation extends prior observations from unselected populations of European descent into a broader multi-ethnic population, and confirms the relevance of these variants in an obese/dysglycaemic population. Despite the robust relationship between adiponectin concentrations and diabetes risk in this cohort, variants in ADIPOQ that relate to adiponectin concentrations do not relate to diabetes risk in this population. ADIPOR1 variants exerted significant effects on diabetes risk distinct from any effect of adiponectin concentrations. © 2012 The Authors. Diabetic Medicine © 2012 Diabetes UK.
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- Billings, Liana K., et al.
(author)
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Variation in maturity-onset diabetes of the young genes influence response to interventions for diabetes prevention
- 2017
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In: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 102:8, s. 2678-2689
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Journal article (peer-reviewed)abstract
- Context: Variation in genes that cause maturity-onset diabetes of the young (MODY) has been associated with diabetes incidence and glycemic traits. Objectives: This study aimed to determine whether genetic variation in MODY genes leads to differential responses to insulin-sensitizing interventions. Design and Setting: This was a secondary analysis of a multicenter, randomized clinical trial, the Diabetes Prevention Program (DPP), involving 27 US academic institutions. We genotyped 22 missense and 221 common variants in the MODY-causing genes in the participants in the DPP. Participants and Interventions: The study included 2806 genotyped DPP participants randomized to receive intensive lifestyle intervention (n = 935), metformin (n = 927), or placebo (n = 944). Main Outcome Measures: Association of MODY genetic variants with diabetes incidence at a median of 3 years and measures of 1-year β-Cell function, insulinogenic index, and oral disposition index. Analyses were stratified by treatment group for significant single-nucleotide polymorphism 3 treatment interaction (Pint, 0.05). Sequence kernel association tests examined the association between an aggregate of rare missense variants and insulinogenic traits. Results: After 1 year, the minor allele of rs3212185 (HNF4A) was associated with improved β-Cell function in the metformin and lifestyle groups but not the placebo group; the minor allele of rs6719578 (NEUROD1) was associated with an increase in insulin secretion in the metformin group but not in the placebo and lifestyle groups. Conclusions: These results provide evidence that genetic variation among MODY genes may influence response to insulin-sensitizing interventions.
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- Franks, Paul W, et al.
(author)
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Childhood obesity, other cardiovascular risk factors, and premature death.
- 2010
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In: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 362:6, s. 485-493
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Journal article (peer-reviewed)abstract
- BACKGROUND: The effect of childhood risk factors for cardiovascular disease on adult mortality is poorly understood. METHODS: In a cohort of 4857 American Indian children without diabetes (mean age, 11.3 years; 12,659 examinations) who were born between 1945 and 1984, we assessed whether body-mass index (BMI), glucose tolerance, and blood pressure and cholesterol levels predicted premature death. Risk factors were standardized according to sex and age. Proportional-hazards models were used to assess whether each risk factor was associated with time to death occurring before 55 years of age. Models were adjusted for baseline age, sex, birth cohort, and Pima or Tohono O'odham Indian heritage. RESULTS: There were 166 deaths from endogenous causes (3.4% of the cohort) during a median follow-up period of 23.9 years. Rates of death from endogenous causes among children in the highest quartile of BMI were more than double those among children in the lowest BMI quartile (incidence-rate ratio, 2.30; 95% confidence interval [CI], 1.46 to 3.62). Rates of death from endogenous causes among children in the highest quartile of glucose intolerance were 73% higher than those among children in the lowest quartile (incidence-rate ratio, 1.73; 95% CI, 1.09 to 2.74). No significant associations were seen between rates of death from endogenous or external causes and childhood cholesterol levels or systolic or diastolic blood-pressure levels on a continuous scale, although childhood hypertension was significantly associated with premature death from endogenous causes (incidence-rate ratio, 1.57; 95% CI, 1.10 to 2.24). CONCLUSIONS: Obesity, glucose intolerance, and hypertension in childhood were strongly associated with increased rates of premature death from endogenous causes in this population. In contrast, childhood hypercholesterolemia was not a major predictor of premature death from endogenous causes.
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- Jablonski, K A, et al.
(author)
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Common variants in 40 genes assessed for diabetes incidence and response to metformin and lifestyle intervention in the diabetes prevention program
- 2010
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In: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; Oct:59(10), s. 2672-2681
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Genome-wide association studies have begun to elucidate the genetic architecture of type 2 diabetes. We examined whether single nucleotide polymorphisms (SNPs) identified through targeted complementary approaches affect diabetes incidence in the at-risk population of the Diabetes Prevention Program (DPP) and whether they influence a response to preventive interventions. RESEARCH DESIGN AND METHODS: We selected SNPs identified by prior genome-wide association studies for type 2 diabetes and related traits, or capturing common variation in 40 candidate genes previously associated with type 2 diabetes, implicated in monogenic diabetes, encoding type 2 diabetes drug targets or drug-metabolizing/transporting enzymes, or involved in relevant physiological processes. We analyzed 1,590 SNPs for association with incident diabetes and their interaction with response to metformin or lifestyle interventions in 2,994 DPP participants. We controlled for multiple hypothesis testing by assessing false discovery rates. RESULTS: We replicated the association of variants in the metformin transporter gene SLC47A1 with metformin response and detected nominal interactions in the AMP kinase (AMPK) gene STK11, the AMPK subunit genes PRKAA1 and PRKAA2, and a missense SNP in SLC22A1, which encodes another metformin transporter. The most significant association with diabetes incidence occurred in the AMPK subunit gene PRKAG2 (hazard ratio 1.24, 95% CI 1.09-1.40, P = 7 × 10(-4)). Overall, there were nominal associations with diabetes incidence at 85 SNPs and nominal interactions with the metformin and lifestyle interventions at 91 and 69 mostly nonoverlapping SNPs, respectively. The lowest P values were consistent with experiment-wide 33% false discovery rates. CONCLUSIONS: We have identified potential genetic determinants of metformin response. These results merit confirmation in independent samples.
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- Li, Josephine H., et al.
(author)
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Identification of Genetic Variation Influencing Metformin Response in a Multiancestry Genome-Wide Association Study in the Diabetes Prevention Program (DPP)
- 2023
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In: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 72:8, s. 1161-1172
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Journal article (peer-reviewed)abstract
- Genome-wide significant loci for metformin response in type 2 diabetes reported elsewhere have not been repli-cated in the Diabetes Prevention Program (DPP). To as-sess pharmacogenetic interactions in prediabetes, we conducted a genome-wide association study (GWAS) in the DPP. Cox proportional hazards models tested associations with diabetes incidence in the metformin (MET; n = 876) and placebo (PBO; n = 887) arms. Multiple linear regression assessed association with 1-year change in metformin-related quantitative traits, adjusted for baseline trait, age, sex, and 10 ancestry principal compo-nents. We tested for gene-by-treatment interaction. No significant associations emerged for diabetes inci-dence. We identified four genome-wide significant variants after correcting for correlated traits (P < 9 × 1029). In the MET arm, rs144322333 near ENOSF1 (minor al-lele frequency [MAF]AFR = 0.07; MAFEUR = 0.002) was associated with an increase in percentage of glycated hemoglobin (per minor allele, b = 0.39 [95% CI 0.28, 0.50]; P = 2.8 × 10212). rs145591055 near OMSR (MAF = 0.10 in American Indians) was associated with weight loss (kilograms) (per G allele, b = 27.55 [95% CI 29.88, 25.22]; P = 3.2 × 10210) in the MET arm. Neither variant was significant in PBO; gene-by-treatment interaction was significant for both variants [P(G×T) < 1.0 × 1024 ]. Replication in individuals with diabetes did not yield significant findings. A GWAS for metformin response in prediabetes revealed novel ethnic-specific associations that require further investigation but may have implications for tailored therapy.
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- Maxwell, Taylor J., et al.
(author)
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Quantitative trait loci, G×E and G×G for glycemic traits : response to metformin and placebo in the Diabetes Prevention Program (DPP)
- 2022
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In: Journal of Human Genetics. - : Springer Science and Business Media LLC. - 1434-5161 .- 1435-232X. ; 67:8, s. 465-473
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Journal article (peer-reviewed)abstract
- The complex genetic architecture of type-2-diabetes (T2D) includes gene-by-environment (G×E) and gene-by-gene (G×G) interactions. To identify G×E and G×G, we screened markers for patterns indicative of interactions (relationship loci [rQTL] and variance heterogeneity loci [vQTL]). rQTL exist when the correlation between multiple traits varies by genotype and vQTL occur when the variance of a trait differs by genotype (potentially flagging G×G and G×E). In the metformin and placebo arms of the DPP (n = 1762) we screened 280,965 exomic and intergenic SNPs, for rQTL and vQTL patterns in association with year one changes from baseline in glycemia and related traits (insulinogenic index [IGI], insulin sensitivity index [ISI], fasting glucose and fasting insulin). Significant (p < 1.8 × 10−7) rQTL and vQTL generated a priori hypotheses of individual G×E tests for a SNP × metformin treatment interaction and secondarily for G×G screens. Several rQTL and vQTL identified led to 6 nominally significant (p < 0.05) metformin treatment × SNP interactions (4 for IGI, one insulin, and one glucose) and 12G×G interactions (all IGI) that exceeded experiment-wide significance (p < 4.1 × 10−9). Some loci are directly associated with incident diabetes, and others are rQTL and modify a trait’s relationship with diabetes (2 diabetes/glucose, 2 diabetes/insulin, 1 diabetes/IGI). rs3197999, an ISI/insulin rQTL, is a possible gene damaging missense mutation in MST1, a gene affecting β-cell apoptosis and insulin secretion. This rQTL may link MST1 with insulin sensitivity where ISI and insulin responses differentially vary by genotype. This study demonstrates evidence for context-dependent effects (G×G & G×E) and the complexity of these T2D-related traits.
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- McCaffery, Jeanne M., et al.
(author)
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Genetic Predictors of Change in Waist Circumference and Waist-to-Hip Ratio With Lifestyle Intervention : The Trans-NIH Consortium for Genetics of Weight Loss Response to Lifestyle Intervention
- 2022
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In: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 71:4, s. 669-676
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Journal article (peer-reviewed)abstract
- Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) associated with waist circumference (WC) and waist-to-hip ratio (WHR) adjusted for BMI (WCadjBMI and WHRadjBMI), but it remains unclear whether these SNPs relate to change in WCadjBMI or WHRadjBMI with lifestyle intervention for weight loss. We hypothesized that polygenic scores (PS) comprised of 59 SNPs previously associated with central adiposity would predict less of a reduction in WCadjBMI or WHRadjBMI at 8-10 weeks in two lifestyle intervention trials, NUGENOB and DiOGenes, and at 1 year in five lifestyle intervention trials, Look AHEAD, Diabetes Prevention Program, Diabetes Prevention Study, DIETFITS, and PREDIMED-Plus. One-SD higher PS related to a smaller 1-year change in WCadjBMI in the lifestyle intervention arms at year 1 and thus predicted poorer response (β = 0.007; SE = 0.003; P = 0.03) among White participants overall and in White men (β = 0.01; SE = 0.004; P = 0.01). At average weight loss, this amounted to 0.20-0.28 cm per SD. No significant findings emerged in White women or African American men for the 8-10-week outcomes or for WHRadjBMI. Findings were heterogeneous in African American women. These results indicate that polygenic risk estimated from these 59 SNPs relates to change in WCadjBMI with lifestyle intervention, but the effects are small and not of sufficient magnitude to be clinically significant.
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