| 1. |
- Lindgren, Cecilia M, et al.
(författare)
-
Genome-wide association scan meta-analysis identifies three Loci influencing adiposity and fat distribution.
- 2009
-
Ingår i: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404. ; 5:6, s. e1000508-
-
Tidskriftsartikel (refereegranskat)abstract
- To identify genetic loci influencing central obesity and fat distribution, we performed a meta-analysis of 16 genome-wide association studies (GWAS, N = 38,580) informative for adult waist circumference (WC) and waist-hip ratio (WHR). We selected 26 SNPs for follow-up, for which the evidence of association with measures of central adiposity (WC and/or WHR) was strong and disproportionate to that for overall adiposity or height. Follow-up studies in a maximum of 70,689 individuals identified two loci strongly associated with measures of central adiposity; these map near TFAP2B (WC, P = 1.9x10(-11)) and MSRA (WC, P = 8.9x10(-9)). A third locus, near LYPLAL1, was associated with WHR in women only (P = 2.6x10(-8)). The variants near TFAP2B appear to influence central adiposity through an effect on overall obesity/fat-mass, whereas LYPLAL1 displays a strong female-only association with fat distribution. By focusing on anthropometric measures of central obesity and fat distribution, we have identified three loci implicated in the regulation of human adiposity.
|
|
| 2. |
- Florez, J, et al.
(författare)
-
Testing of diabetes-associated WFS1 polymorphisms in the Diabetes Prevention Program
- 2007
-
Ingår i: Diabetologia. - : Springer. - 0012-186X .- 1432-0428. ; 51:3, s. 451-457
-
Tidskriftsartikel (refereegranskat)abstract
- Aims/hypothesis: Wolfram syndrome (diabetes insipidus, diabetes mellitus, optic atrophy and deafness) is caused by mutations in the WFS1 gene. Recently, single nucleotide polymorphisms (SNPs) in WFS1 have been reproducibly associated with type 2 diabetes. We therefore examined the effects of these variants on diabetes incidence and response to interventions in the Diabetes Prevention Program (DPP), in which a lifestyle intervention or metformin treatment was compared with placebo.Methods: We genotyped the WFS1 SNPs rs10010131, rs752854 and rs734312 (H611R) in 3,548 DPP participants and performed Cox regression analysis using genotype, intervention and their interactions as predictors of diabetes incidence. We also evaluated the effect of these SNPs on insulin resistance and beta cell function at 1 year.Results: Although none of the three SNPs was associated with diabetes incidence in the overall cohort, white homozygotes for the previously reported protective alleles appeared less likely to develop diabetes in the lifestyle arm. Examination of the publicly available Diabetes Genetics Initiative genome-wide association dataset revealed that rs10012946, which is in strong linkage disequilibrium with the three WFS1 SNPs (r 2 = 0.88–1.0), was associated with type 2 diabetes (allelic odds ratio 0.85, 95% CI 0.75–0.97, p = 0.026). In the DPP, we noted a trend towards increased insulin secretion in carriers of the protective variants, although for most SNPs this was seen as compensatory for the diminished insulin sensitivity.Conclusions/interpretation: The previously reported protective effect of select WFS1 alleles may be magnified by a lifestyle intervention. These variants appear to confer an improvement in beta cell function.
|
|
| 3. |
|
|
| 4. |
- Brito, Ema C, 1961-, et al.
(författare)
-
PPARGC1A sequence variation and cardiovascular risk-factor levels : a study of the main genetic effects and gene x environment interactions in children from the European youth heart study
- 2009
-
Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 52:4, s. 609-613
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS: The PPARGC1A gene coactivates multiple nuclear transcription factors involved in cellular energy metabolism and vascular stasis. In the present study, we genotyped 35 tagging polymorphisms to capture all common PPARGC1A nucleotide sequence variations and tested for association with metabolic and cardiovascular traits in 2,101 Danish and Estonian boys and girls from the European Youth Heart Study, a multicentre school-based cross-sectional cohort study. METHODS: Fasting plasma glucose concentrations, anthropometric variables and blood pressure were measured. Habitual physical activity and aerobic fitness were objectively assessed using uniaxial accelerometry and a maximal aerobic exercise stress test on a bicycle ergometer, respectively. RESULTS: In adjusted models, nominally significant associations were observed for BMI (rs10018239, p = 0.039), waist circumference (rs7656250, p = 0.012; rs8192678 [Gly482Ser], p = 0.015; rs3755863, p = 0.02; rs10018239, beta = -0.01 cm per minor allele copy, p = 0.043), systolic blood pressure (rs2970869, p = 0.018) and fasting glucose concentrations (rs11724368, p = 0.045). Stronger associations were observed for aerobic fitness (rs7656250, p = 0.005; rs13117172, p = 0.008) and fasting glucose concentrations (rs7657071, p = 0.002). None remained significant after correcting for the number of statistical comparisons. We proceeded by testing for gene x physical activity interactions for the polymorphisms that showed nominal evidence of association in the main effect models. None of these tests was statistically significant. CONCLUSIONS/INTERPRETATION: Variants at PPARGC1A may influence several metabolic traits in this European paediatric cohort. However, variation at PPARGC1A is unlikely to have a major impact on cardiovascular or metabolic health in these children.
|
|
| 5. |
- Eriksson, Margareta K., 1955-, et al.
(författare)
-
A 3-year randomized trial of lifestyle intervention for cardiovascular risk reduction in the primary care setting : the Swedish Björknäs study
- 2009
-
Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 4:4, s. e5195-
-
Tidskriftsartikel (refereegranskat)abstract
- Background Successfully transferring the findings of expensive and tightly controlled programmes of intensive lifestyle modification to the primary care setting is necessary if such knowledge is to be of clinical utility. The objective of this study was to test whether intensive lifestyle modification, shown previously in tightly-controlled clinical trials to be efficacious for diabetes risk-reduction among high-risk individuals, can reduce cardiovascular risk factor levels in the primary care setting. Methodology / Principal Findings The Swedish Björknäs study was a randomized controlled trial conducted from 2003 to 2006 with follow-up on cardiovascular risk factors at 3, 12, 24 and 36 months. A total of 151 middle-aged men and women at moderate- to high-risk of cardiovascular disease from northern Sweden were randomly assigned to either an intensive lifestyle intervention (n=75) or control (n=76) group. The intervention was based broadly on the protocol of the Diabetes Prevention Program. The three-month intervention period was administered in the primary care setting and consisted of supervised exercise sessions and diet counselling, followed by regular group meetings during three years. The control group was given general advice about diet and exercise and received standard clinical care. Outcomes were changes in anthropometrics, aerobic fitness, self-reported physical activity, blood pressure, and metabolic traits. At 36 months post-randomisation, intensive lifestyle modification reduced waist circumference (–2.2cm: p=0.001), waist-hip ratio (–0.02: p<0.0001), systolic blood pressure (–4.9mmHg: p=0.036), and diastolic blood pressure (–1.6mmHg: p=0.005), and improved aerobic fitness (5%; p=0.038). Changes in lipid or glucose values did not differ statistically between groups. At 36 months, self-reported time spent exercising and total physical activity had increased more in the intervention group than in the control group (p<0.001). Conclusion / Significance A program of intensive lifestyle modification undertaken in the primary health care setting can favourably influence cardiovascular risk-factor profiles in high-risk individuals.
|
|
| 6. |
|
|
| 7. |
- Franks, Paul W, et al.
(författare)
-
Assessing gene-treatment interactions at the FTO and INSIG2 loci on obesity-related traits in the Diabetes Prevention Program
- 2008
-
Ingår i: Diabetologia. - New York : Springer. - 0012-186X .- 1432-0428. ; 51:12, s. 2214-2223
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS: The single nucleotide polymorphism (SNP) rs9939609 in the fat mass and obesity associated gene (FTO) and the rs7566605 SNP located 10 kb upstream of the insulin-induced gene 2 gene (INSIG2) have been proposed as risk factors for common obesity.METHODS: We tested for genotype-treatment interactions on changes in obesity-related traits in the Diabetes Prevention Program (DPP). The DPP is a randomised controlled trial of 3,548 high-risk individuals from 27 participating centres throughout the USA who were originally randomised to receive metformin, troglitazone, intensive lifestyle modification or placebo to prevent the development of type 2 diabetes. Measures of adiposity from computed tomography were available in a subsample (n = 908). This report focuses on the baseline and 1 year results.RESULTS: The minor A allele at FTO rs9939609 was positively associated with baseline BMI (p = 0.003), but not with baseline adiposity or the change at 1 year in any anthropometric trait. For the INSIG2 rs7566605 genotype, the minor C allele was associated with more subcutaneous adiposity (second and third lumbar vertebrae [L2/3]) at baseline (p = 0.04). During follow-up, CC homozygotes lost more weight than G allele carriers (p = 0.009). In an additive model, we observed nominally significant gene-lifestyle interactions on weight change (p = 0.02) and subcutaneous (L2/3 [p = 0.01] and L4/5 [p = 0.03]) and visceral (L2/3 [p = 0.02]) adipose areas. No statistical evidence of association with physical activity energy expenditure or energy intake was observed for either genotype.CONCLUSIONS/INTERPRETATION: Within the DPP study population, common variants in FTO and INSIG2 are nominally associated with quantitative measures of obesity, directly and possibly by interacting with metformin or lifestyle intervention.
|
|
| 8. |
- Franks, Paul W., et al.
(författare)
-
Interaction Between Physical Activity and Genetic Factors in Complex Metabolic Disease
- 2008
-
Ingår i: Energy Metabolism and Obesity. - Totowa : Humana Press. - 9781588296719 - 9781603271394 ; , s. 155-173
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Obesity and diabetes have become increasingly prevalent during the past century. Concomitant with this rise, the consumption of trans-fatty acids and processed carbohydrates is likely to have increased and physical activity levels declined. However, the rates at which obesity and diabetes have increased differ across people of varying ethnicities living in the same environment, suggesting the presence of interaction between ethnic-specific factors, such as genes, and changing environments and lifestyles. Quantifying these interactions is difficult because the interaction effect is often small, and precise measurement of lifestyle factors, such as diet and habitual physical activity, is difficult. Conventional interaction studies aim to test whether the magnitude of the association between the lifestyle exposures and the disease outcome is different in those who carry the variant allele at a given locus by comparison with those who do not. Because exercising skeletal muscle is a major site for glucose and lipid metabolism, variants in the genes that are located within muscle and that are up-regulated in response to physical activity present interesting candidates for testing in studies of gene x physical activity interaction in diabetes. However, numerous methodological limitations seriously hinder attempts to test such hypotheses. This chapter describes (1) a brief review of studies that provide evidence of gene x physical activity interaction in diabetes (and related traits), (2) functional evidence for interaction between genetic factors and physical activity in metabolic dysregulation, and (3) some common methodological issues that face the study of gene x environment interaction in human populations.
|
|
| 9. |
- Jonsson, A, et al.
(författare)
-
Assessing the effect of interaction between an FTO variant (rs9939609) and physical activity on obesity in 15,925 Swedish and 2,511 Finnish adults.
- 2009
-
Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 52:7, s. 1334-1338
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS: Recent reports have suggested that genotypes at the FTO locus interact with physical activity to modify levels of obesity-related traits. We tested this hypothesis in two non-diabetic population-based cohorts, the first from southern Sweden and the second from the Botnia region of western Finland. METHODS: In total 2,511 Finnish and 15,925 Swedish non-diabetic middle-aged adults were genotyped for the FTO rs9939609 variant. Physical activity was assessed by questionnaires and standard clinical procedures were conducted, including measures of height and weight and glucose regulation. Tests of gene x physical activity interaction were performed using linear interaction effects to determine whether the effect of this variant on BMI is modified by physical activity. RESULTS: The minor A allele at rs9939609 was associated with higher BMI in both cohorts, with the per allele difference in BMI being about 0.13 and 0.43 kg/m(2) in the Swedish and Finnish cohorts, respectively (p < 0.0001). The test of interaction between physical activity and the rs9939609 variant on BMI was not statistically significant after controlling for age and sex in either cohort (Sweden: p = 0.71, Finland: p = 0.18). CONCLUSIONS/INTERPRETATION: The present report does not support the notion that physical activity modifies the effects of the FTO rs9939609 variant on obesity risk in the non-diabetic Swedish or Finnish adults studied here.
|
|
| 10. |
|
|
