The Arg82Cys Polymorphism of the Protein Nepmucin Implies a Role in HDL Metabolism.

Context: Blood lipid levels are linked to the risk of cardiovascular disease and regulated by genetic factors. A low-frequency polymorphism Arg82Cys (rs72836561) in the membrane protein nepmucin, encoded by CD300LG, is associated with lower fasting concentration of high-density lipoprotein cholesterol (HDLc) and higher fasting triglycerides. However, whether the variant is linked to postprandial lipids and glycemic status remains elusive. Objective: Here, we augment the genetic effect of Arg82Cys on fasting plasma concentrations of HDL subclasses, postprandial lipemia after a standardized high-fat meal, and glycemic status to further untangle its role in HDL metabolism. Methods: We elucidated fasting associations with HDL subclasses in a population-based cohort study (Oxford BioBank, OBB), including 4522 healthy men and women. We investigated fasting and postprandial consequences on HDL metabolism in recall-by-genotype (RbG) studies (fasting: 20 carrier/20 noncarrier; postprandial: 7 carrier/17 noncarrier), and shed light on the synergistic interaction with glycemic status. Results: A lower fasting plasma concentration of cholesterol in large HDL particles was found in healthy male carriers of the Cys82 polymorphism compared to noncarriers, both in the OBB (P = .004) and RbG studies (P = .005). In addition, the Cys82 polymorphism was associated with low fasting plasma concentrations of ApoA1 (P = .008) in the OBB cohort. On the contrary, we did not find differences in postprandial lipemia or 2-hour plasma glucose levels. Conclusion: Taken together, our results indicate an association between the Arg82Cys variant and a lower concentration of HDL particles and HDLc, especially in larger HDL subclasses, suggesting a link between nepmucin and HDLc metabolism or maturation.

Indirect comparison of efficacy of dupilumab versus mepolizumab and omalizumab for severe type 2 asthma.

This indirect comparison of dupilumab, mepolizumab and omalizumab for patients with severe type 2 asthma fulfilling start-up criteria for more than one drug shows no significant efficacy differences https://bit.ly/3pK9Nf9.

Efficacy of omalizumab in children, adolescents, and adults with severe allergic asthma: a systematic review, meta-analysis, and call for new trials using current guidelines for assessment of severe asthma.

BACKGROUND: Omalizumab is approved for treating severe allergic asthma from age 6, but the definition of severe asthma including a systematic assessment to rule out difficult-to-treat asthma has changed since the drug was approved in 2003. METHODS: We conducted a systematic review and meta-analysis of two critical (exacerbation rate, oral corticosteroid (OCS) treatment) and eight important clinical outcomes in children, adolescents and adults, and specifically searched papers for systematic assessment of severe asthma. RESULTS: Adults: seven studies (n = 2159) ascertaining exacerbation rate showing a 37% (95% CI 21-50) reduction in favor of omalizumab, larger than the pre-specified minimal clinically important difference (MCID) of 25%. Only one open-label study (n = 82) was identified assessing the percentage of patients experiencing reduction of OCS-maintenance treatment showing a significantly greater decrease in the omalizumab group (- 45% vs. + 18.3%, p = 0.002). Children and adolescents: four studies (n = 1551) reported data on exacerbations (no meta-analysis conducted), showed overall improvements in exacerbation rate and some passed MCID. No OCS studies were identified. No included studies provided systematic assessment of severe asthma according to current guidelines. CONCLUSIONS: Omalizumab provides clinically relevant improvements in exacerbation rate among children, adolescents, and adults and in OCS-reduction among adults. New studies incorporating a guideline-approached definition of severe asthma are warranted.

Efficacy, adverse events, and inter-drug comparison of mepolizumab and reslizumab anti-IL-5 treatments of severe asthma - a systematic review and meta-analysis.

Background: New, complex, and expensive therapies targeting Interleukin-5 (IL-5) to treat severe eosinophilic asthma are emerging. Objective: To assess efficacy, adverse events, and inter-drug comparison of mepolizumab and reslizumab for treating severe eosinophilic asthma. Design: A systematic review and meta-analysis on randomized, placebo-controlled, clinical trials elucidating two critical (exacerbation rate and oral corticosteroid (OCS) use) and six important clinical outcomes on the efficacy and safety of mepolizumab and reslizumab. Results: Five studies (N = 2197) contributed with data for exacerbation rate, showing a reduction of 53% (95% CI 46; 59) in favour of anti-IL-5, corresponding to -0.94 annual exacerbations (95% CI -1.08;-0.82), thus exceeding the predefined minimal clinical important difference (MCID) of 25% reduction of the estimated ≥2 annual exacerbations. Quality of evidence was considered moderate, with low heterogeneity in study findings (I2 = 0%). One study (N = 135) contributed with data on percentage of patients experiencing ≥50% reduction inoral corticosteroid treatment, showing an effect of 20% (95% CI 2.3;47) in favour of anti-IL-5 treatment (mepolizumab), thus exceeding the predefined MCID of 10%. Quality of evidence was considered low. Compared to placebo, anti-IL-5 showed significant improvements in lung function, asthma control, and asthma-related quality of life, but below the MCIDs. No differences were observed for serious adverse events and number of patients, who dropped out. No studies evaluating sickleave or head-to-head comparisons were identified. By indirect comparison, we found no significant difference between mepolizumab and reslizumab in any ofthe predefined clinical outcomes. OCS treatment reduction could not be compared due to lack of reslizumab studies investigating this outcome. Conclusions: Mepolizumab and reslizumab provide significant and clinically relevant improvements in exacerbation rate and OCS reduction. Indirect, inter-study comparisons revealed no differences between the anti-IL-5 drugs in efficacy or safety measures.

Publisher Correction: Re-analysis of public genetic data reveals a rare X-chromosomal variant associated with type 2 diabetes.

In the originally published version of this Article, the affiliation details for Santi González, Jian'an Luan and Claudia Langenberg were inadvertently omitted. Santi González should have been affiliated with 'Barcelona Supercomputing Center (BSC), Joint BSC-CRG-IRB Research Program in Computational Biology, 08034 Barcelona, Spain', and Jian'an Luan and Claudia Langenberg should have been affiliated with 'MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK'. Furthermore, the abstract contained an error in the SNP ID for the rare variant in chromosome Xq23, which was incorrectly given as rs146662057 and should have been rs146662075. These errors have now been corrected in both the PDF and HTML versions of the Article.

Re-analysis of public genetic data reveals a rare X-chromosomal variant associated with type 2 diabetes.

The reanalysis of existing GWAS data represents a powerful and cost-effective opportunity to gain insights into the genetics of complex diseases. By reanalyzing publicly available type 2 diabetes (T2D) genome-wide association studies (GWAS) data for 70,127 subjects, we identify seven novel associated regions, five driven by common variants (LYPLAL1, NEUROG3, CAMKK2, ABO, and GIP genes), one by a low-frequency (EHMT2), and one driven by a rare variant in chromosome Xq23, rs146662057, associated with a twofold increased risk for T2D in males. rs146662057 is located within an active enhancer associated with the expression of Angiotensin II Receptor type 2 gene (AGTR2), a modulator of insulin sensitivity, and exhibits allelic specific activity in muscle cells. Beyond providing insights into the genetics and pathophysiology of T2D, these results also underscore the value of reanalyzing publicly available data using novel genetic resources and analytical approaches.

Increasing insulin resistance accentuates the effect of triglyceride-associated loci on serum triglycerides during 5 years.

Blood concentrations of triglycerides are influenced by genetic factors as well as a number of environmental factors, including adiposity and glucose homeostasis. The aim was to investigate the association between a serum triglyceride weighted genetic risk score (wGRS) and changes in fasting serum triglyceride level over 5 years and to test whether the effect of the wGRS was modified by 5 year changes of adiposity, insulin resistance, and lifestyle factors. A total of 3,474 nondiabetic individuals from the Danish Inter99 cohort participated in both the baseline and 5 year follow-up physical examinations and had information on the wGRS comprising 39 genetic variants. In a linear regression model adjusted for age, sex, and baseline serum triglyceride, the wGRS was associated with increased serum triglyceride levels over 5 years [per allele effect = 1.3% (1.0-1.6%); P = 1.0 × 10-17]. This triglyceride-increasing effect of the wGRS interacted with changes in insulin resistance (Pinteraction = 1.5 × 10-6). This interaction indicated that the effect of the wGRS was stronger in individuals who became more insulin resistant over 5 years. In conclusion, our findings suggest that increased genetic risk load is associated with a larger increase in fasting serum triglyceride levels in nondiabetic individuals during 5 years of follow-up. This effect of the wGRS is accentuated by increasing insulin resistance.

Functional and genetic epidemiological characterisation of the FFAR4 (GPR120) p.R270H variant in the Danish population.

BACKGROUND: p.R270H (rs116454156) in the long chain fatty acid 7TM receptor FFAR4 (GPR120) which results in impaired Gαq (Gq) coupled signalling, has been associated with obesity. We aimed to extend the functional in vitro analyses of p.R270H and to investigate the association with obesity and glucose-related traits in the Danish population. METHODS: Surface expression, Gq and Gi coupled signalling as well as ß-arrestin recruitment were examined in vitro. p.R270H was genotyped using the exome chip array in 11 479 Danish adult individuals. Of these 4391 were obese and 4415 were normal weight. Association with quantitative metabolic traits comprised 8720 non-diabetic individuals. RESULTS: p.R270H showed reduced surface expression of FFAR4. Ligand-independent activity was eliminated and strongly impaired through the Gq and Gi signalling pathways, respectively. The ligand-induced maximal signalling efficacy of p.R270H was reduced only through the Gq pathway. The p.R270H variant did not affect ß-arrestin recruitment. p.R270H was not associated with increased risk of obesity nor increased fasting plasma glucose levels in the Danish study populations. Nor was it associated with these two traits in the European Network for Genetic and Genomic Epidemiology consortium data (N=34 901-71 175; p>0.70). It was also not associated with waist-hip ratio, glucose metabolism during an oral glucose tolerance test, lipid levels or with markers of adiposity (leptin, adiponectin), inflammation (high-sensitive C reactive protein; hs-CRP) and liver function (alanine aminotransferase) in the Danish population (p>0.05). CONCLUSIONS: We demonstrate that p.R270H of FFAR4 impairs Gq and Gi signalling of FFAR4 in vitro; however, this impaired signalling for p.R270H does not translate into associations with human metabolic phenotypes in the investigated populations.

Genetic risk score of 46 type 2 diabetes risk variants associates with changes in plasma glucose and estimates of pancreatic ß-cell function over 5 years of follow-up.

More than 40 genetic risk variants for type 2 diabetes have been validated. We aimed to test whether a genetic risk score associates with the incidence of type 2 diabetes and with 5-year changes in glycemic traits and whether 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 had improved 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 ß-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 ß-cell function. Individuals who gain weight may be more susceptible to the cumulative impact of type 2 diabetes risk variants on fasting plasma glucose.

Type 2 diabetes risk alleles near BCAR1 and in ANK1 associate with decreased ß-cell function whereas risk alleles near ANKRD55 and GRB14 associate with decreased insulin sensitivity in the Danish Inter99 cohort.

CONTEXT: Recently, 10 novel type 2 diabetes (T2D) susceptibility single nucleotide polymorphisms (SNPs) in ZMIZ1, ANK1, KLHDC5, TLE1, ANKRD55, CILP2, MC4R, BCAR1, HMG20A, and GRB14 loci were discovered in MetaboChip-genotyped populations of European ancestry. OBJECTIVE: The aim of the present study was to characterize prediabetic quantitative traits underlying these SNP associations and to calculate the amount of interindividual variation in glycemic traits explained by these and previous T2D susceptibility variants. DESIGN AND PARTICIPANTS: A total of 5739 Danish individuals naive to glucose-lowering medication were included in quantitative trait studies, and case-control analyses were performed in 1892 patients with T2D and 6603 normoglycemic control subjects. Participants without known T2D underwent an oral glucose tolerance test, and measures of insulin release and sensitivity were estimated from insulinogenic, disposition, BIGTT, and Matsuda indexes. RESULTS: We confirmed associations of ZMIZ1, KLHDC5, CILP2, HMG20A, ANK1, ANKRD55, and BCAR1 with T2D. The risk T allele of BCAR1 rs7202877 associated with decreased disposition index (P = .02). The C allele of ANK1 rs516946 associated with decreased insulinogenic (P = .005) and disposition (P = .002) indexes. The G allele of ANKRD55 rs459193 associated with decreased Matsuda index (P = .02) adjusted for waist circumference. The C allele of GRB14 rs13389219 associated with both increased insulinogenic (P = .04) and decreased Matsuda (P = .05) indexes. All validated European T2D variants still only explained a few percentage points of glycemic trait variation. CONCLUSIONS: BCAR1 rs7202877 may mediate its diabetogenic impact through impaired ß-cell function, but this finding needs to be replicated in independent studies. In addition, we substantiated previous evidence that ANK1 rs516946 confers impaired insulin release and that ANKRD55 rs459193 and GRB14 rs13389219 associate with insulin resistance.

The birth weight lowering C-allele of rs900400 near LEKR1 and CCNL1 associates with elevated insulin release following an oral glucose challenge.

BACKGROUND AND AIM: The first genome-wide association study on birth weight was recently published and the most significant associated birth weight lowering variant was the rs900400 C-allele located near LEKR1 and CCNL1. We aimed to replicate the association with birth weight in the Danish Inter99 study and furthermore to evaluate associations between rs900400 and indices of insulin secretion and insulin sensitivity obtained by oral glucose tolerance tests in adults from the Danish Inter99 study and the Finnish, Metabolic Syndrome in Men (METSIM) sample. METHODS: For 4,744 of 6,784 Inter99 participants, midwife journals were traced through the Danish State Archives and association of rs900400 with birth weight was examined. Associations between rs900400 and fasting serum insulin, fasting plasma glucose, insulinogenic index, homeostasis model assessment of insulin resistance (HOMA-IR) and disposition index were studied in 5,484 Danish and 6,915 Finnish non-diabetic individuals and combined in meta-analyses. RESULTS: The C-allele of rs900400 was associated with a 22.1 g lower birth weight ([-41.3;-3.0], P = 0.024) per allele. Moreover, in combined analyses of the Danish Inter99 study and the Finnish METSIM study we found that the birth weight lowering allele was associated with increased insulin release measured by the insulinogenic index (ß = 2.25% [0.59; 3.91], P = 0.008) and with an increased disposition index (ß = 1.76% [0.04; 3.49], P = 0.05). CONCLUSION: The birth weight lowering effect of the C-allele of rs900400 located near LEKR1 and CCNL1 was replicated in the Danish population. Furthermore the C-allele was associated with increased insulin response following oral glucose stimulation in a meta-analysis based on Danish and Finnish non-diabetic individuals.

Do gene variants influencing adult adiposity affect birth weight? A population-based study of 24 loci in 4,744 Danish individuals.

BACKGROUND: Several obesity risk alleles affecting adult adiposity have been identified by the recent wave of genome wide association studies. We aimed to examine the potential effect of these variants on fetal body composition by investigating the variants in relation to birth weight and ponderal index of the newborn. METHODOLOGY/PRINCIPAL FINDINGS: Midwife records from the Danish State Archives provided information on mother's age, parity, as well as birth weight, birth length and prematurity of the newborn in 4,744 individuals of the population-based Inter99 study. Twenty-four risk alleles showing genome-wide associations with adult BMI and/or waist circumference were genotyped. None of the 24 risk variants tested showed an association with birth weight or ponderal index after correction for multiple testing. Birth weight was divided into three categories low (≤10(th) percentile), normal (10(th)-90(th) percentile) and high birth weight (≥90th percentile) to allow for non-linear associations. There was no difference in the number of risk alleles between the groups (p = 0.57). No interactions between each risk allele and birth weight in the prediction of adult BMI were observed. An obesity risk score was created by summing up risk alleles. The risk score did not associate with fetal body composition. Moreover there was no interaction between the risk score and birth weight/ponderal index in the prediction of adult BMI. CONCLUSION: 24 common variants associated with adult adiposity did not affect or interact with birth weight among Danes suggesting that the effects of these variants predominantly arise in the post-natal life.

Further evidence that mutations in INS can be a rare cause of Maturity-Onset Diabetes of the Young (MODY).

BACKGROUND: Insulin gene (INS) mutations have recently been described as a common cause of permanent neonatal diabetes (PNDM) and a rare cause of diabetes diagnosed in childhood or adulthood. METHODS: INS was sequenced in 116 maturity-onset diabetes of the young (MODYX) patients (n = 48 Danish and n = 68 Czech), 83 patients with gestational diabetes mellitus (GDM), 34 type 1 diabetic patients screened negative for glutamic acid decarboxylase (GAD), and 96 glucose tolerant individuals. The control group was randomly selected from the population-based sampled Inter99 study. RESULTS: One novel heterozygous mutation c.17G>A, R6H, was identified in the pre-proinsulin gene (INS) in a Danish MODYX family. The proband was diagnosed at 20 years of age with mild diabetes and treated with diet and oral hypoglycaemic agent. Two other family members who carried the INS R6H were diagnosed with diabetes when 51 years old and with GDM when 27 years old, respectively. A fourth mutation carrier had normal glucose tolerance when 20 years old. Two carriers of INS R6H were also examined twice with an oral glucose tolerance test (OGTT) with 5 years interval. They both had a approximately 30% reduction in beta-cell function measured as insulinogenic index. In a Czech MODYX family a previously described R46Q mutation was found. The proband was diagnosed at 13 years of age and had been treated with insulin since onset of diabetes. Her mother and grandmother were diagnosed at 14 and 35 years of age, respectively, and were treated with oral hypoglycaemic agents and/or insulin. CONCLUSION: Mutations in INS can be a rare cause of MODY and we conclude that screening for mutations in INS should be recommended in MODYX patients.

MTNR1B G24E variant associates With BMI and fasting plasma glucose in the general population in studies of 22,142 Europeans.

OBJECTIVE: Common variants in the melatonin receptor type 1B (MTNR1B) locus have been shown to increase fasting plasma glucose (FPG) and the risk of type 2 diabetes. The aims of this study were to evaluate whether nonsynonymous variants in MTNR1B associate with monogenic forms of hyperglycemia, type 2 diabetes, or related metabolic traits. RESEARCH DESIGN AND METHODS: MTNR1B was sequenced in 47 probands with clinical maturity-onset diabetes of the young (MODY), in 51 probands with early-onset familial type 2 diabetes, and in 94 control individuals. Six nonsynonymous variants (G24E, L60R, V124I, R138C, R231H, and K243R) were genotyped in up to 22,142 Europeans. Constitutive and melatonin-induced signaling was characterized for the wild-type melatonin receptor type 1B (MT2) and the 24E, 60R, and 124I MT2 mutants in transfected COS-7 cells. RESULTS: No mutations in MTNR1B were MODY specific, and none of the investigated MTNR1B variants associated with type 2 diabetes. The common 24E variant associated with increased prevalence of obesity (odds ratio 1.20 [1.08-1.34]; P = 8.3 x 10(-4)) and increased BMI (beta = 0.5 kg/m(2); P = 1.2 x 10(-5)) and waist circumference (beta = 1.2 cm; P = 9 x 10(-6)) in combined Danish and French study samples. 24E also associated with decreased FPG (beta = -0.08 mmol/l; P = 9.2 x 10(-4)) in the Danish Inter99 population. Slightly decreased constitutive activity was observed for the MT2 24E mutant, while the 124I and 60R mutants displayed considerably decreased or completely disrupted signaling, respectively. CONCLUSIONS: Nonsynonymous mutations in MTNR1B are not a common cause of MODY or type 2 diabetes among Danes. MTNR1B 24E associates with increased body mass and decreased FPG. Decreased MT2 signaling does apparently not directly associate with FPG or type 2 diabetes.

Variation in the gene encoding Krüppel-like factor 7 influences body fat: studies of 14 818 Danes.

OBJECTIVE: KLF7 encodes Krüppel-like factor (KLF) 7, a member of the KLF family of transcription factors, initially shown to play important roles in cellular development and differentiation, and reported to be specifically involved in adipogenesis. Several single nucleotide polymorphisms (SNPs) have been identified in KLF7, of which the A-allele of rs2302870 has been associated with type 2 diabetes in a Japanese population; however, a possible association of KLF7 SNPs with obesity has not been investigated. We aimed to identify variation in the putative promoter region, the coding regions, exon/intron boundaries, and 3'-UTR of KLF7, and to examine identified variants in relation to obesity, type 2 diabetes, and related quantitative traits in Danish individuals. METHODS: Identified variants were investigated for association with type 2 diabetes in 8777 individuals and with obesity in 14 818 individuals. RESULTS: We identified four common SNPs in low pairwise linkage disequilibrium; three in the putative promoter region (-1119 G>A, -963 C>A (rs7568369), and -614 G>A) and IVS2+35092 A>C (rs2302870). We failed to confirm an association between rs2302870 and type 2 diabetes. Neither was rs7568369 associated with type 2 diabetes; however, the minor A-allele of rs7568369 protected against obesity (OR=0.90 (0.84-0.96), P=0.001) and in studies of quantitative traits (n=5,535) the variant associated with decreased body mass index (P=0.002) and waist circumference (P=0.003). The -1119 G>A and -614 G>A variants were not associated with obesity or type 2 diabetes. CONCLUSION: We identified a novel association between the minor A-allele of KLF7 rs7568369 and protection against obesity in the Danish population.

Association of variants in the sterol regulatory element-binding factor 1 (SREBF1) gene with type 2 diabetes, glycemia, and insulin resistance: a study of 15,734 Danish subjects.

OBJECTIVE: We evaluated the association of variants in the sterol regulatory element-binding factor 1 gene (SREBF1) with type 2 diabetes. Due to the previous inconclusive quantitative trait associations, we also did studies of intermediate quantitative phenotypes. RESEARCH DESIGN AND METHODS: We genotyped four variants in SREBF1 in the population-based Inter99 cohort (n = 6,070), the Danish ADDITION study (n = 8,662), and in additional type 2 diabetic patients (n = 1,002). The case-control studies involved 2,980 type 2 diabetic patients and 4,522 glucose-tolerant subjects. RESULTS: The minor alleles of rs2297508, rs11868035, and rs1889018 (linkage disequilibrium R(2) = 0.6-0.8) associated with a modestly increased risk of type 2 diabetes (rs2297508: OR 1.17 [95% CI 1.05-1.30], P = 0.003), which was confirmed in meta-analyses of all published studies (rs2297508 G-allele: 1.08 [1.03-1.14] per allele, P = 0.001). The diabetes-associated alleles also associated strongly with a higher plasma glucose at 30 and 120 min and serum insulin at 120 min during an oral glucose tolerance test (all P < 0.006) and the minor allele of rs1889018 with a surrogate measure of insulin sensitivity (P = 0.03). Furthermore, the diabetes-associated alleles associated with a modestly increased A1C level in the population-based Inter99 of middle-aged subjects and in the ADDITION study of high-risk individuals (P = 0.006 and P = 0.008, respectively). CONCLUSIONS: We associate sequence variation in SREBF1 with a modestly increased predisposition to type 2 diabetes. In the general population, the diabetes-associated alleles are discreetly associated with hyperglycemia presumably due to decreased insulin sensitivity. Because sterol regulatory element-binding protein-1c is a mediator of insulin action, the findings are consistent with the presence of a yet undefined subtle loss-of-function SREBF1 variant.

Studies of association of variants near the HHEX, CDKN2A/B, and IGF2BP2 genes with type 2 diabetes and impaired insulin release in 10,705 Danish subjects: validation and extension of genome-wide association studies.

OBJECTIVE: In the present study, we aimed to validate the type 2 diabetes susceptibility alleles identified in six recent genome-wide association studies in the HHEX/KIF11/IDE (rs1111875), CDKN2A/B (rs10811661), and IGF2BP2 (rs4402960) loci, as well as the intergenic rs9300039 variant. Furthermore, we aimed to characterize quantitative metabolic risk phenotypes of the four variants. RESEARCH DESIGN AND METHODS: The variants were genotyped in the population-based Inter99 cohort (n = 5,970), the ADDITION Study (n = 1,626), a population-based sample of young healthy subjects (n = 377), and in additional type 2 diabetic case (n = 2,111) and glucose-tolerant (n = 521) subjects. The case-control studies involved a total of 4,089 type 2 diabetic patients and 5,043 glucose-tolerant control subjects. RESULTS: We validated association of variants near HHEX/KIF11/IDE, CDKN2A/B, and IGF2BP2 with type 2 diabetes. Interestingly, in middle-aged people, the rs1111875 C-allele of HHEX/KIF11/IDE strongly associated with lower acute insulin response during an oral glucose tolerance test (P = 6 x 10(-7)). In addition, decreased insulin release following intravenous tolbutamide injection was observed in young healthy subjects (P = 0.02). Also, a reduced insulin release was observed for the CDKN2A/B rs10811661 T-allele after both oral and intravenous glucose challenges (P = 0.001 and P = 0.009, respectively). CONCLUSIONS: We validate that variants in the proximity of the HHEX/KIF11/IDE, CDKN2A/B, and IFG2BP2 loci associate with type 2 diabetes. Importantly, variations within the HHEX/KIF11/IDE and CDKN2A/B loci confer impaired glucose- and tolbutamide-induced insulin release in middle-aged and young healthy subjects, suggesting a role for these variants in the pathogenesis of pancreatic beta-cell dysfunction.