Camilla H Sandholt

IT University of Copenhagen, København, Capital Region, Denmark

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Publications (32)232.4 Total impact

  • Camilla H Sandholt · Oluf Pedersen

    No preview · Article · Oct 2015 · Nature Reviews Endocrinology
  • Mette Korre Andersen · Camilla Helene Sandholt
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    ABSTRACT: Since 2007, discovery of genetic variants associated with general obesity and fat distribution has advanced tremendously through genome-wide association studies (GWAS). Currently, the number of robustly associated loci is 190. Even though these loci explain <3 % of the variance, they have provided us a still emerging picture of genomic localization, frequency and effect size spectra, and hints of functional implications. The translation into biological knowledge has turned out to be an immense task. However, in silico enrichment analyses of genes involved in specific pathways or expressed in specific tissues have the power to suggest biological mechanisms underlying obesity. Inspired by this, we highlight genes in five loci potentially mechanistically linked to leptin-receptor trafficking and signaling in primary cilia. The clinical application of genetic knowledge as prediction, prevention, or treatment strategies is unfortunately still far from reality. Thus, despite major advances, further research is warranted to solve one of the greatest health problems in modern society.
    No preview · Article · Sep 2015
  • Camilla H. Sandholt · Niels Grarup · Oluf Pedersen · Torben Hansen
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    ABSTRACT: The decade anniversary for genome-wide association studies (GWAS) is approaching, and this experimental approach has commenced a deeper understanding of the genetics underlying complex diseases. In obesity genetics the GIANT (Genetic Investigation of ANthropometric Traits) consortium has played a crucial role, recently with two comprehensive meta-analyses, one focusing on general obesity, analyzing body-mass index (BMI) and the other on fat distribution, focusing on waist-hip ratio adjusted for BMI. With the in silico methods applied in these two studies as the pivot, this review looks into some of the biological knowledge, beginning to emerge from the intricate genomic background behind the genetic determinants of human adiposity. These include synaptic dysfunction, where GWAS pinpoint potential new mechanisms in pathways already known to be linked with obesity.
    No preview · Article · Sep 2015 · Molecular and Cellular Endocrinology
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    ABSTRACT: In Europeans, 45 genetic risk variants for coronary artery disease (CAD) have been identified in genome-wide association studies. We constructed a genetic risk score (GRS) of these variants to estimate the effect on incidence and clinical predictability of myocardial infarction (MI) and CAD. Genotype was available from 6041 Danes. An unweighted GRS was constructed by making a summated score of the 45 known genetic CAD risk variants. Registries provided information (mean follow-up = 11.6 years) on CAD (n = 374) and MI (n = 124) events. Cox proportional hazard estimates with age as time scale was adjusted for sex, BMI, type 2 diabetes mellitus and smoking status. Analyses were also stratified either by sex or median age (below or above 45 years of age). We estimated GRS contribution to MI prediction by assessing net reclassification index (NRI) and integrated discrimination improvement (IDI) added to the European SCORE for 10-year MI risk prediction. The GRS associated significantly with risk of incident MI (allele-dependent hazard ratio (95%CI): 1.06 (1.02-1.11), p = 0.01) but not with CAD (p = 0.39). Stratification revealed association of GRS with MI in men (1.06 (1.01-1.12), p = 0.02) and in individuals above the median of 45.11 years of age (1.06 (1.00-1.12), p = 0.03). There was no interaction between GRS and gender (p = 0.90) or age (p = 0.83). The GRS improved neither NRI nor IDI. The GRS of 45 GWAS identified risk variants increase the risk of MI in a Danish cohort. The GRS did not improve NRI or IDI beyond the performance of conventional European SCORE risk factors. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
    No preview · Article · Mar 2015 · Atherosclerosis
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    ABSTRACT: -There are several well-established lifestyle factors influencing dyslipidemia and currently, 157 genetic susceptibility loci have been reported to be associated with serum lipid levels at genome-wide statistical significance. However, the interplay between lifestyle risk factors and these susceptibility loci has not been fully elucidated. We tested if genetic risk scores (GRS) of lipid-associated SNPs associate with fasting serum lipid traits and if the effects are modulated by lifestyle factors or estimates of metabolic health. -The SNPs were genotyped in two Danish cohorts: Inter99 (n=5,961) for discovery analyses and Health2006 (n=2,565) for replication. Based on published effect sizes of SNPs associated with circulating fasting levels of total cholesterol, LDL-cholesterol, HDL-cholesterol or triglyceride, four weighted GRS (wGRS) were constructed. In a cross-sectional design, we investigated if the effect of these wGRSs on lipid levels were modulated by diet, alcohol consumption, physical activity and smoking or the individual metabolic health status as estimated from BMI, waist circumference and insulin resistance assessed using HOMA-IR. All four lipid wGRSs associated strongly with their respective trait (from P=3.3×10(-69) to P=1.1×10(-123)). We found interactions between the triglyceride wGRS and BMI and waist circumference on fasting triglyceride levels in Inter99 and replicated these findings in Health2006 (Pinteraction=9.8×10(-5) and 2.0×10(-5), respectively in combined analysis). -Our findings suggest that individuals who are obese may be more susceptible to the cumulative genetic burden of triglyceride SNPs. Therefore, it is suggested that especially these genetically at-risk individuals may benefit more from targeted interventions aiming at obesity prevention.
    Full-text · Article · Feb 2015 · Circulation Cardiovascular Genetics
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    ABSTRACT: Context: Type 2 diabetes (T2D) prevalence is spiralling globally and knowledge of its pathophysiological signatures is crucial for a better understanding and treatment of the disease. Objective: We aimed to discover underlying coding genetic variants influencing fasting serum levels of nine biomarkers associated with T2D: adiponectin, C-reactive protein (CRP), ferritin, heat-shock 70kDa protein 1B (HSPA1B), insulin-like growth factor binding protein 1 (IGFBP1) and 2 (IGFBP2), interleukin 18 (IL18), interleukin 2 receptor alpha (IL2RA), and leptin. Design and Participants: A population-based sample of 6,215 adult Danes was genotyped for 16,340 coding single-nucleotide polymorphisms (SNPs) and tested for association with each biomarker. Identified loci were tested for association with T2D through a large scale meta-analysis involving up to 17,024 T2D cases and up to 64,186 controls. Results: We discovered 11 associations between SNPs and five distinct biomarkers at a study-wide P < 3.4 × 10(-7). Nine associations were novel: IL18: BIRC6, RAD17, MARVELD2; ferritin: F5; IGFBP1: SERPING1, KLKB, GCKR, CELSR2 and HSPA1B: CFH. Three of the identified loci (CELSR2, HNF1A and GCKR) were significantly associated with T2D of which the association with the CELSR2 locus has not been shown previously. Conclusion: The identified loci influence processes related to insulin signalling, cell communication, immune function, apoptosis, DNA repair, and oxidative stress, all of which could provide a rationale for novel diabetes therapeutic strategies.
    Full-text · Article · Jan 2015 · Journal of Clinical Endocrinology & Metabolism
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    ABSTRACT: Aims/hypothesis: Elevated serum ferritin levels are associated with an increased risk of type 2 diabetes, but the nature of this association remains elusive. The aim of this study was to test the hypothesis that an elevated fasting serum ferritin level is associated with an increased risk of type 2 diabetes due to its association with impaired beta cell function and decreased insulin sensitivity. Methods: We investigated 6,392 individuals from the Danish general population. Surrogate measures of beta cell function and insulin sensitivity were calculated for approximately 6,100 individuals based on OGTT examinations. Results: The ORs for type 2 diabetes were 4.2 (95% CI 2.4, 7.2) for the highest vs the lowest quintile of serum ferritin, and 17 (95% CI 8.9, 33) for serum ferritin levels ≥97.5th percentile vs <20th percentile. Elevated serum ferritin levels were associated with elevated plasma glucose levels at 0, 30 and 120 min (p < 0.001), elevated serum insulin levels at 0 and 120 min (p = 0.02 and p < 0.001), decreased beta cell function estimated as the insulinogenic index and corrected insulin response (p < 0.001), and decreased insulin sensitivity estimated by the Matsuda index of insulin sensitivity and HOMA-IR (p < 0.001). Whereas the association with impaired beta cell function was present in both men and women, the association with decreased insulin sensitivity was observed among men and older women but not among younger women. Conclusions/interpretation: Elevated fasting serum ferritin levels are associated with surrogate measures of both impaired beta cell function and decreased insulin sensitivity. Menopause seems to modify the association with insulin sensitivity.
    Full-text · Article · Dec 2014 · Diabetologia
  • Niels Grarup · Camilla H Sandholt · Torben Hansen · Oluf Pedersen
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    ABSTRACT: During the past 7 years, genome-wide association studies have shed light on the contribution of common genomic variants to the genetic architecture of type 2 diabetes, obesity and related intermediate phenotypes. The discoveries have firmly established more than 175 genomic loci associated with these phenotypes. Despite the tight correlation between type 2 diabetes and obesity, these conditions do not appear to share a common genetic background, since they have few genetic risk loci in common. The recent genetic discoveries do however highlight specific details of the interplay between the pathogenesis of type 2 diabetes, insulin resistance and obesity. The focus is currently shifting towards investigations of data from targeted array-based genotyping and exome and genome sequencing to study the individual and combined effect of low-frequency and rare variants in metabolic disease. Here we review recent progress as regards the concepts, methodologies and derived outcomes of studies of the genetics of type 2 diabetes and obesity, and discuss avenues to be investigated in the future within this research field.
    No preview · Article · May 2014 · Diabetologia
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    ABSTRACT: Background The GIANT consortium identified 14 loci in European Ancestry (EA) individuals associated with waist-to-hip ratio adjusted for BMI (WHR). These loci are wide and narrowing the signals remains necessary.ResultsTwelve of 14 loci identified in GIANT EA samples retained strong associations with WHR in our joint EA/AA analysis (log-Bayes factor>6.1). Trans-ethnic analyses at five loci (TBX15-WARS2, LYPLAL1, ADAMTS9, LY86 and ITPR2-SSPN) substantially narrowed the signals to smaller sets of variants, some of which are in regions that have evidence of regulatory activity.Conclusion By leveraging varying linkage disequilibrium structures across different populations, SNPs with strong signals and narrower credible sets from trans-ethnic meta-analysis of central obesity provide more precise localizations of potential functional variants and suggest a possible regulatory role.Methods Meta-analysis results for WHR were obtained from 77,167 EA participants from GIANT and 23,564 African Ancestry (AA) participants from the African Ancestry Anthropometry Genetics Consortium. For fine mapping we interrogated SNPs within ±250 kb flanking regions of 14 previously reported index SNPs from loci discovered in EA populations by performing trans-ethnic meta-analysis of results from the EA and AA meta-analyses. We applied a Bayesian approach that leverages allelic heterogeneity across populations to combine meta-analysis results and aids in fine-mapping shared variants at these locations. We annotated variants using information from the ENCODE Consortium and Roadmap Epigenomics Project to prioritize variants for possible functionality.
    Full-text · Article · Apr 2014 · Human Molecular Genetics
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    ABSTRACT: Meta-analyses have suggested an effect of MTHFR C677T genotype (rs1801133), a proxy for blood total homocysteine, on cardiovascular disease (CVD) in populations with low population dietary folate. The aim was to examine the association and effect modification by serum folate and vitamin B12 levels between MTHFR and CVD-related outcomes in a general population with no mandatory folic acid fortification policy. The study population included 13,748 adults retrieved from pooling of four population-based studies conducted in Denmark. MTHFR genotype, serum folate (measured in approximately 9,356 individuals), and serum vitamin B12 (9,215 individuals), hypertension, and dyslipidemia were measured at baseline, and participants were followed for a mean of 10.5-11.7 years in central registries for diagnoses of stroke (623 incidents), ischaemic heart disease (IHD) (835 incidents), and all-cause mortality (1,272 incidents). The MTHFR genotype (TT vs. CC/CT) was not associated with hypertension [OR (95 % CI) 1.09 (0.95-1.25)], dyslipidemia [OR (95 % CI) 0.97 (0.84-1.11)], stroke [HR (95 % CI) 0.92 (0.69-1.23)], and all-cause mortality [HR (95 % CI) 0.94 (0.77-1.14)], either overall, or in participants with low serum folate or B12 status (P values for interactions 0.15-0.94). Individuals with the MTHFR TT genotype had a higher risk of IHD (HR (95 % CI) 1.38 (1.11-1.71)), but this association was not modified by folate status (P value for interaction 0.45). Our results do not support a causal relationship between homocysteine and CVD. However, we cannot exclude a direct causal effect of MTHFR C677T genotype on IHD.
    No preview · Article · Jan 2014 · European Journal of Nutrition
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    ABSTRACT: Numerous obesity loci have been identified using genome-wide association studies. A UK study indicated that physical activity may attenuate the cumulative effect of 12 of these loci, but replication studies are lacking. Therefore, we tested whether the aggregate effect of these loci is diminished in adults of European ancestry reporting high levels of physical activity. Twelve obesity-susceptibility loci were genotyped or imputed in 111,421 participants. A genetic risk score (GRS) was calculated by summing the BMI-associated alleles of each genetic variant. Physical activity was assessed using self-administered questionnaires. Multiplicative interactions between the GRS and physical activity on BMI were tested in linear and logistic regression models in each cohort, with adjustment for age, age2, sex, study center (for multicenter studies), and the marginal terms for physical activity and the GRS. These results were combined using meta-analysis weighted by cohort sample size. The meta-analysis yielded a statistically significant GRS × physical activity interaction effect estimate (Pinteraction = 0.015). However, a statistically significant interaction effect was only apparent in North American cohorts (n = 39,810, Pinteraction = 0.014 vs. n = 71,611, Pinteraction = 0.275 for Europeans). In secondary analyses, both the FTO rs1121980 (Pinteraction = 0.003) and the SEC16B rs10913469 (Pinteraction = 0.025) variants showed evidence of SNP × physical activity interactions. This meta-analysis of 111,421 individuals provides further support for an interaction between physical activity and a GRS in obesity disposition, although these findings hinge on the inclusion of cohorts from North America, indicating that these results are either population-specific or non-causal.
    Full-text · Article · Jul 2013 · PLoS Genetics
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    ABSTRACT: More than 40 genetic risk variants for type 2 diabetes have been validated. We aimed to test if a genetic risk score associates with the incidence of type 2 diabetes and with 5-year changes in glycemic traits and if the effects were modulated by changes in BMI and lifestyle.The Inter99 study population was genotyped for 46 variants and a genetic risk score was constructed. During a median follow-up of 11 years 327 of 5,850 individuals developed diabetes. Physical examinations and oral glucose tolerance tests were performed at baseline and after 5 years (n=3,727).The risk of incident type 2 diabetes was increased with a hazard ratio of 1.06 [95%CI 1.03-1.08] per risk allele. While the population in general improved their glucose regulation during the 5-year follow-up period, each additional allele in the genetic risk score was associated with a relative increase in fasting, 30-min and 120-min plasma glucose values and a relative decrease in measures of beta-cell function over the 5-year period, whereas indices of insulin sensitivity were unaffected. The effect of the genetic risk score on 5-year changes in fasting plasma glucose was stronger in individuals who increased their BMI.In conclusion, a genetic risk score based on 46 variants associated strongly with incident type 2 diabetes and 5-year changes in plasma glucose and beta-cell function. Individuals who gain weight may be more susceptible to the cumulative impact of type 2 diabetes risk variants on fasting plasma glucose.
    Full-text · Article · Jul 2013 · Diabetes
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    ABSTRACT: Genome-wide association studies have mainly relied on common HapMap sequence variations. Recently, sequencing approaches have allowed analysis of low frequency and rare variants in conjunction with common variants, thereby improving the search for functional variants and thus the understanding of the underlying biology of human traits and diseases. Here, we used a large Icelandic whole genome sequence dataset combined with Danish exome sequence data to gain insight into the genetic architecture of serum levels of vitamin B12 (B12) and folate. Up to 22.9 million sequence variants were analyzed in combined samples of 45,576 and 37,341 individuals with serum B12 and folate measurements, respectively. We found six novel loci associating with serum B12 (CD320, TCN2, ABCD4, MMAA, MMACHC) or folate levels (FOLR3) and confirmed seven loci for these traits (TCN1, FUT6, FUT2, CUBN, CLYBL, MUT, MTHFR). Conditional analyses established that four loci contain additional independent signals. Interestingly, 13 of the 18 identified variants were coding and 11 of the 13 target genes have known functions related to B12 and folate pathways. Contrary to epidemiological studies we did not find consistent association of the variants with cardiovascular diseases, cancers or Alzheimer's disease although some variants demonstrated pleiotropic effects. Although to some degree impeded by low statistical power for some of these conditions, these data suggest that sequence variants that contribute to the population diversity in serum B12 or folate levels do not modify the risk of developing these conditions. Yet, the study demonstrates the value of combining whole genome and exome sequencing approaches to ascertain the genetic and molecular architectures underlying quantitative trait associations.
    Full-text · Article · Jun 2013 · PLoS Genetics
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    ABSTRACT: [This corrects the article on p. e40376 in vol. 7.].
    No preview · Article · Sep 2012 · PLoS ONE
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    ABSTRACT: Non-alcoholic fatty liver disease (NAFLD) is a common condition, associated with hepatic insulin resistance and the metabolic syndrome including hyperglycaemia and dyslipidemia. We aimed at studying the potential impact of the NAFLD-associated PNPLA3 rs738409 G-allele on NAFLD-related metabolic traits in hyperglycaemic individuals. The rs738409 variant was genotyped in the population-based Inter99 cohort examined by an oral glucose-tolerance test, and a combined study-sample consisting of 192 twins (96 twin pairs) and a sub-set of the Inter99 population (n = 63) examined by a hyperinsulinemic euglycemic clamp (n(total) = 255). In Inter99, we analyzed associations of rs738409 with components of the WHO-defined metabolic syndrome (n = 5,847) and traits related to metabolic disease (n = 5,663). In the combined study sample we elucidated whether the rs738409 G-allele altered hepatic or peripheral insulin sensitivity. Study populations were divided into individuals with normal glucose-tolerance (NGT) and with impaired glucose regulation (IGR). The case-control study showed no associations with components of the metabolic syndrome or the metabolic syndrome. Among 1,357 IGR individuals, the rs738409 G-allele associated with decreased fasting serum triglyceride levels (per allele effect(β) = -9.9% [-14.4%;-4.0% (95% CI)], p = 5.1×10(-5)) and fasting total cholesterol (β = -0.2 mmol/l [-0.3;-0.01 mmol/l(95% CI)], p = 1.5×10(-4)). Meta-analyses showed no impact on hepatic or peripheral insulin resistance in carriers of the rs738409 G-allele. Our findings suggest that the G-allele of PNPLA3 rs738409 associates with reduced fasting levels of cholesterol and triglyceride in individuals with IGR.
    Full-text · Article · Jul 2012 · PLoS ONE
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    C H Sandholt · T Hansen · O Pedersen
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    ABSTRACT: Obesity and related complications are major health burdens. Almost 700 million adults are currently obese globally and the prevalence is predicted to rise towards 2030. The sudden change of lifestyle with physical inactivity and excessive calorie intake undoubtedly have a major part of the epidemic development; however, some individuals seem to be more prone to be affected by an unhealthy lifestyle than others. Hence, genetic predisposition also has an essential role in determining disease susceptibility and response to lifestyle factors. Since the introduction of genome-wide association studies (GWAS), the success of identifying obesity susceptibility variants have increased, and a total of 32 variants have been identified associating genome-wide significantly with body mass index (BMI) and 18 with measures of fat distribution during four overall obesity GWAS waves. However, the immediate success of the GWAS approach has eased off, but the proportion of explained variance for BMI by the identified obesity variants remains low. This review suggests and discusses new initiatives to take GWAS of obesity to the next level, including gene-environment interactions as modulating/masking factors, low-frequent or rare variants and ways to address such analyses, and finally reflections about the applicability of epigenetic modifications when elucidating the genetic background of obesity.
    Preview · Article · Jul 2012 · Nutrition & Diabetes
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    ABSTRACT: Gene-lifestyle interactions have been suggested to contribute to the development of type 2 diabetes. Glucose levels 2 h after a standard 75-g glucose challenge are used to diagnose diabetes and are associated with both genetic and lifestyle factors. However, whether these factors interact to determine 2-h glucose levels is unknown. We meta-analyzed single nucleotide polymorphism (SNP) × BMI and SNP × physical activity (PA) interaction regression models for five SNPs previously associated with 2-h glucose levels from up to 22 studies comprising 54,884 individuals without diabetes. PA levels were dichotomized, with individuals below the first quintile classified as inactive (20%) and the remainder as active (80%). BMI was considered a continuous trait. Inactive individuals had higher 2-h glucose levels than active individuals (β = 0.22 mmol/L [95% CI 0.13-0.31], P = 1.63 × 10(-6)). All SNPs were associated with 2-h glucose (β = 0.06-0.12 mmol/allele, P ≤ 1.53 × 10(-7)), but no significant interactions were found with PA (P > 0.18) or BMI (P ≥ 0.04). In this large study of gene-lifestyle interaction, we observed no interactions between genetic and lifestyle factors, both of which were associated with 2-h glucose. It is perhaps unlikely that top loci from genome-wide association studies will exhibit strong subgroup-specific effects, and may not, therefore, make the best candidates for the study of interactions.
    Full-text · Article · Mar 2012 · Diabetes
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    ABSTRACT: The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA) may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166) and nine studies of children and adolescents (n = 19,268). All studies identified to have data on the FTO rs9939609 variant (or any proxy [r(2)>0.8]) and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active) in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A-) allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20-1.26), but PA attenuated this effect (p(interaction)  = 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio  = 1.22/allele, 95% CI 1.19-1.25) than in the inactive group (odds ratio  = 1.30/allele, 95% CI 1.24-1.36). No such interaction was found in children and adolescents. The association of the FTO risk allele with the odds of obesity is attenuated by 27% in physically active adults, highlighting the importance of PA in particular in those genetically predisposed to obesity.
    Full-text · Article · Nov 2011 · PLoS Medicine
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    ABSTRACT: Waist-hip ratio (WHR) is a measure of body fat distribution and a predictor of metabolic consequences independent of overall adiposity. WHR is heritable, but few genetic variants influencing this trait have been identified. We conducted a meta-analysis of 32 genome-wide association studies for WHR adjusted for body mass index (comprising up to 77,167 participants), following up 16 loci in an additional 29 studies (comprising up to 113,636 subjects). We identified 13 new loci in or near RSPO3, VEGFA, TBX15-WARS2, NFE2L3, GRB14, DNM3-PIGC, ITPR2-SSPN, LY86, HOXC13, ADAMTS9, ZNRF3-KREMEN1, NISCH-STAB1 and CPEB4 (P = 1.9 × 10−9 to P = 1.8 × 10−40) and the known signal at LYPLAL1. Seven of these loci exhibited marked sexual dimorphism, all with a stronger effect on WHR in women than men (P for sex difference = 1.9 × 10−3 to P = 1.2 × 10−13). These findings provide evidence for multiple loci that modulate body fat distribution independent of overall adiposity and reveal strong gene-by-sex interactions.
    Full-text · Article · Oct 2011 · Nature Genetics
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    ABSTRACT: Genome-wide association studies have identified novel WHR and BMI susceptibility loci. The aim of this study was to elucidate if any of these loci had an effect on quantitative measures of glucose homeostasis, including estimates of insulin release and insulin sensitivity in an epidemiological setting. By applying an additive genetic model, 14 WHR-associated gene variants and 18 BMI-associated variants were investigated for their relationships with glucose-related metabolic traits in treatment-naive individuals from the population-based Inter99 study sample (n = 6,039). Of the variants associated with BMI, the QPCTL rs2287019 C allele was associated with an increased insulinogenic index of 7.4% per risk allele (p = 4.0 × 10⁻⁷) and increased disposition index of 5.6% (p = 6.4 × 10⁻⁵). The LRP1B rs2890652 C allele was associated with insulin resistance, showing a 3.3% increase (p = 0.0011) using the HOMA-insulin resistance (HOMA-IR) index and a 2.2% reduction (p = 0.0014) with the Matsuda index. Of the variants associated with WHR, LYPLAL1/SLC30A10 rs4846567 G allele carriers showed a 5.2% lower HOMA-IR (p = 0.00086) in women, indicating improved insulin sensitivity. Female carriers of the VEGFA rs6905288 A allele were insulin resistant, with a 3.7% increase in HOMA-IR (p = 0.00036) and 4.0% decrease in Matsuda index (p = 2 × 10⁻⁴). Our correlative findings from analysing single-locus data suggest that some variation in validated BMI and WHR loci are associated with either increased or decreased insulin sensitivity and thereby potentially with metabolically healthy or metabolically unhealthy subsets of obesity. The results call for testing in larger study samples and for further physiological exploration of the possible metabolic implications of these loci.
    Full-text · Article · Sep 2011 · Diabetologia