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O Pedersen

Publications and source records attributed to O Pedersen.

At least 55 records · Page 3Linked to original sources

Studies of variability in the islet amyloid polypeptide gene in relation to Type 2 diabetes.

AIMS: To explore whether the coding region of the islet amyloid polypeptide (IAPP) gene contains genetic variants associated with Type 2 diabetes and whether a previously reported association of the promoter variant -132g-->a with Type 2 diabetes could be reproduced in Danish Caucasians. METHODS: The coding region was analyzed using single strand conformation polymorphism (SSCP) and heteroduplex analysis in 192 Type 2 diabetic patients. Restriction fragment length polymorphism (RFLP) was employed to screen for the promoter variant in 414 Type 2 diabetic patients and 182 glucose-tolerant control subjects. RESULTS: The SSCP analysis identified an IVS+75a-->g variant in two patients. The frequency of heterozygous carriers of the promoter variant in the case-control study was 4.1% (17/414) and 7.1% (13/182), respectively. Odds ratio of the prevalence of Type 2 diabetes in carriers compared with non-carriers was estimated to be 0.47 (95% confidence interval 0.19, 1.15). CONCLUSION: Neither variability in the coding region of the IAPP gene nor the -132g-->a promoter variant was associated with Type 2 diabetes among the studied Danish Caucasians.

Amyloid↗

Rehospitalization for respiratory syncytial virus infection in infants with extremely low gestational age or birthweight in Denmark.

AIM: To determine the risk of rehospitalization for respiratory syncytial virus (RSV) infection during the first 2 y of life in extremely preterm infants. METHODS: Records on all rehospitalizations during the first 2 living years of all infants born with gestational age <28 wk or birthweight <1,000g during 1994 and 1995 in Denmark were retrospectively reviewed. RESULTS: Among 240 eligible infants, 43 (18%) had been rehospitalized 48 times owing to RSV. In infants (n = 210) without CLD the risk of rehospitalization for RSV was 16%, whereas in infants with CLD (n = 30) it was 30% (p = 0.065). Eighteen infants (38%) required respiratory support (supplemental oxygen only 3, continuous positive airway pressure 14, mechanical ventilation 1). Apart from CLD the only factor that could be associated with increased risk of hospitalization for RSV was discharge during autumn (p = 0.05). No infant died from RSV infection. CONCLUSION: The high rate of rehospitalization for RSV in extremely preterm infants in Denmark, especially in infants with CLD, should lead to considerations concerning more widespread use of prophylaxis against RSV in these infants.

Denmark↗

The pathophysiology of diabetes involves a defective amplification of the late-phase insulin response to glucose by glucose-dependent insulinotropic polypeptide-regardless of etiology and phenotype.

The effect of the insulinotropic incretin hormone, glucagon-like peptide-1 (GLP-1), is preserved in typical middle-aged, obese, insulin-resistant type 2 diabetic patients, whereas a defective amplification of the so-called late-phase plasma insulin response (20-120 min) to glucose by the other incretin hormone, glucose-dependent insulinotropic polypeptide (GIP), is seen in these patients. The aim of the present investigation was to evaluate plasma insulin and C-peptide responses to GLP-1 and GIP in five groups of diabetic patients with etiology and phenotype distinct from the obese type 2 diabetic patients. We studied (six in each group): 1) patients with diabetes mellitus secondary to chronic pancreatitis; 2) lean type 2 diabetic patients (body mass index < 25 kg/m(2)); 3) patients with latent autoimmune diabetes in adults; 4) diabetic patients with mutations in the HNF-1alpha gene [maturity-onset diabetes of the young (MODY)3]; and 5) newly diagnosed type 1 diabetic patients. All participants underwent three hyperglycemic clamps (2 h, 15 mM) with continuous infusion of saline, 1 pmol GLP-1 (7-36)amide/kg body weight.min or 4 pmol GIP pmol/kg body weight.min. The early-phase (0-20 min) plasma insulin response tended to be enhanced by both GIP and GLP-1, compared with glucose alone, in all five groups. In contrast, the late-phase (20-120 min) plasma insulin response to GIP was attenuated, compared with the plasma insulin response to GLP-1, in all five groups. Significantly higher glucose infusion rates were required during the late phase of the GLP-1 stimulation, compared with the GIP stimulation. In conclusion, lack of GIP amplification of the late-phase plasma insulin response to glucose seems to be a consequence of diabetes mellitus, characterizing most, if not all, forms of diabetes.

Adult↗

Hyperproinsulinemia and proinsulin-to-insulin ratios in Swedish middle-aged men: association with glycemia and insulin resistance but not with family history of diabetes.

Elevated proinsulin and proinsulin/insulin ratios are features of abnormal beta-cell function in type 2 diabetes. The participation of genetic factors is disputed. The authors wished to investigate relations between family history of diabetes on one hand and proinsulin as well as proinsulin/immunoreactive insulin ratios on the other. A large, population-based sample of Swedish men aged 35-54 years in 1992 was studied. Subjects without known diabetes were selected either to have a strong family history of diabetes (n = 1,619) or no history of the disease (n = 1,495). An oral glucose tolerance test detected 172 subjects with impaired glucose tolerance and 55 subjects with previously unknown diabetes according to World Health Organization 1985 criteria. In multiple regression analysis, fasting levels of proinsulin and proinsulin/insulin ratios were positively associated both with the 2-hour glucose level (as a continuous variable) and with obesity, whereas a negative association was found with birth weight. No association was found with family history of diabetes or with chronologic age. These findings indicate that elevated proinsulin and proinsulin/insulin ratios are secondary to increased demands on beta-cell secretion induced by hyperglycemia and insulin resistance with no discernible influence of family history of diabetes.

Adult↗

The genetic abnormality in the beta cell determines the response to an oral glucose load.

AIMS/HYPOTHESIS: We assessed how the role of genes genetic causation in causing maturity-onset diabetes of the young (MODY) alters the response to an oral glucose tolerance test (OGTT). METHODS: We studied OGTT in 362 MODY subjects, from seven European centres; 245 had glucokinase gene mutations and 117 had Hepatocyte Nuclear Factor -1 alpha ( HNF-1alpha) gene mutations. RESULTS: BMI and age were similar in the genetically defined groups. Fasting plasma glucose (FPG) was less than 5.5 mmol/l in 2 % glucokinase subjects and 46 % HNF-1 alpha subjects ( p < 0.0001). Glucokinase subjects had a higher FPG than HNF-1 alpha subjects ([means +/- SD] 6.8 +/- 0.8 vs 6.0 +/- 1.9 mmol/l, p < 0.0001), a lower 2-h value (8.9 +/- 2.3 vs 11.2 +/- 5.2 mmol/l, p < 0.0001) and a lower OGTT increment (2-h - fasting) (2.1 +/- 2.3 vs 5.2 +/- 3.9 mmol/l, p < 0.0001). The relative proportions classified as diabetic depended on whether fasting (38 % vs 22 %, glucokinase vs HNF-1 alpha) or 2-h values (19 % vs 44 %) were used. Fasting and 2-h glucose values were not correlated in the glucokinase subjects ( r = -0.047, p = 0.65) but were strongly correlated in HNF-1 alpha subjects ( r = 0.8, p < 0.001). Insulin concentrations were higher in the glucokinase subjects throughout the OGTT. CONCLUSION/INTERPRETATION: The genetic cause of the beta-cell defect results in clear differences in both the fasting glucose and the response to an oral glucose load and this can help diagnostic genetic testing in MODY. OGTT results reflect not only the degree of hyperglycaemia but also the underlying cause.

Adult↗

A meta-analytic investigation of linkage and association of common leptin receptor (LEPR) polymorphisms with body mass index and waist circumference.

METHODS: We analyzed data pooled from nine studies on the human leptin receptor (LEPR) gene for the association of three alleles (K109R, Q223R and K656N) of LEPR with body mass index (BMI; kg/m(2)) and waist circumference (WC). A total of 3263 related and unrelated subjects from diverse ethnic backgrounds including African-American, Caucasian, Danish, Finnish, French Canadian and Nigerian were studied. We tested effects of individual alleles, joint effects of alleles at multiple loci, epistatic effects among alleles at different loci, effect modification by age, sex, diabetes and ethnicity, and pleiotropic genotype effects on BMI and WC. RESULTS: We found that none of the effects were significant at the 0.05 level. Heterogeneity tests showed that the variations of the non-significant effects are within the range of sampling variation. CONCLUSIONS: We conclude that, although certain genotypic effects could be population-specific, there was no statistically compelling evidence that any of the three LEPR alleles is associated with BMI or WC in the overall population.

Alleles↗

Association studies between microsatellite markers within the gene encoding human 11beta-hydroxysteroid dehydrogenase type 1 and body mass index, waist to hip ratio, and glucocorticoid metabolism.

Two isozymes of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) interconvert active cortisol (F) and inactive cortisone (E). 11beta-HSD1 is an oxo-reductase (E to F) expressed in several glucocorticoid target tissues, including liver and adipose tissue, where it facilitates glucocorticoid-induced gluconeogenesis and adipocyte differentiation, respectively. We have isolated a full-length HSD11B1 genomic clone; the gene is more than 30 kb in length, not 9 kb in length as previously reported, principally due to a large intron 4. Two polymorphic (CA)(n) repeats have been characterized within intron 4: a CA(19) repeat 2.7 kb 3' of exon 4 and a CA(15) repeat 3 kb 5' of exon 5. The microsatellites, CA(19) and CA(15), were PCR amplified using fluorescent primers and were genotyped on an ABI 377 DNA sequencer from DNA of 413 normal individuals enrolled in the MONICA study of cardiovascular risk factors and 557 Danish men (ADIGEN study), of whom 234 were obese [body mass index (BMI), >/=31 kg/m(2) ] at draft board examination and 323 were randomly selected controls from the draftee population with BMI below 31 kg/m(2) (mean +/- SE, 21.7 +/- 0.41). Genotypic data from the normal MONICA cohort was compared with gender, 5beta-tetrahydrocortisol+5alpha-tetrahydrocortisol/tetrahydrocortisone ratio, and waist to hip (W:H) ratio. When analyzed by allele length (0, 1, or 2 short alleles) for the CA(19) marker, there was a trend toward a higher 5beta-tetrahydrocortisol+5alpha-tetrahydrocortisol/tetrahydrocortisone ratio (P = 0.058) and an increased W:H ratio (2 vs. 0.1 short; P(c) = 0.10) with overrepresentation of short alleles. The opposite was true for the CA(15) locus, with longer alleles at this locus predicting increased 11beta-HSD1 activity, particularly in females. Genotypic data from the ADIGEN case-control population was compared with clinical markers of obesity such as BMI and W:H ratio. There was no significant difference in the distribution of either microsatellite marker between lean and obese groups. Allele distributions were binomial, as seen for the MONICA cohort, and the data were split accordingly (zero, one, or two short alleles). No significant association was seen between grouped alleles and the clinical parameters. No association was observed between HSD11B1 genotype and BMI in either population. These data suggest that 11beta-HSD1 is not a major factor in explaining genetic susceptibility to obesity per se. However, weak associations between HSD11B1 genotype, increased 11beta-HSD1 activity, and W:H ratio suggest that polymorphic variability at the HSD11B1 locus may influence susceptibility to central obesity through enhanced 11beta-HSD1 activity (E to F conversion) in visceral adipose tissue.

11-beta-Hydroxysteroid Dehydrogenase Type 2↗

Treatment with NS3623, a novel Cl-conductance blocker, ameliorates erythrocyte dehydration in transgenic SAD mice: a possible new therapeutic approach for sickle cell disease.

The dehydration of sickle red blood cells (RBCs) through the Ca-activated K channel depends on the parallel movement of Cl ions. To study whether Cl-conductance block might prevent dehydration of sickle RBCs, a novel Cl-conductance inhibitor (NS3623) was characterized in vitro using RBCs from healthy donors and sickle cell patients and in vivo using normal mice and a transgenic mouse model of sickle cell disease (SAD mice). In vitro, NS3623 reversibly blocked human RBC Cl-conductance (g(Cl)) with an IC(50) value of 210 nmol/L and a maximal block of 95%. In vivo, NS3623 inhibited RBC g(Cl) after oral administration to normal mice (ED(50) = 25 mg/kg). Although g(Cl), at a single dose of 100 mg/kg, was still 70% inhibited 5 hours after dosing, the inhibition disappeared after 24 hours. Repeated administration of 100 mg/kg twice a day for 10 days caused no adverse effects; therefore, this regimen was chosen as the highest dosing for the SAD mice. SAD mice were treated for 3 weeks with 2 daily administrations of 10, 35, and 100 mg/kg NS3623, respectively. The hematocrit increased, and the mean corpuscular hemoglobin concentration decreased in all groups with a concomitant increase in the intracellular cation content. A loss of the densest red cell population was observed in conjunction with a shift from a high proportion of sickled to well-hydrated discoid erythrocytes, with some echinocytes present at the highest dosage. These data indicate feasibility for the potential use of Cl-conductance blockers to treat human sickle cell disease.

Anemia, Sickle Cell↗

Studies of the variability of the hepatocyte nuclear factor-1beta (HNF-1beta / TCF2) and the dimerization cofactor of HNF-1 (DcoH / PCBD) genes in relation to type 2 diabetes mellitus and beta-cell function.

Mutations in the homeodomain-containing transcription factor hepatocyte nuclear factor-1beta (HNF-1beta) are known to cause a rare subtype of maturity-onset diabetes of the young (MODY5), which is associated with early-onset progressive non-diabetic renal dysfunction. To investigate whether mutations in HNF-1 are implicated in the pathogenesis of MODY or late-onset diabetes with and without nephropathy in Danish Caucasians we examined the HNF-1beta (TCF2) and the dimerization cofactor of HNF-1 (DCoH, PCBD) genes for mutations in 11 MODY probands, 28 type 2 diabetic patients with nephropathy, and 46 type 2 diabetic patients with an impaired beta-cell function by combined single-strand conformation polymorphism (SSCP) and heteroduplex analysis. Analysis of the promoter and nine exons including intron-exon boundaries of the HNF-1beta gene revealed one novel silent polymorphism and three previously reported intronic variants. The silent polymorphism (I91I) was found in one patient with late-onset type 2 diabetes. One of the intronic variant (IVS6+26T-->C) was examined further. Among 584 type 2 diabetic patients the allelic frequency was 13.1% (11.2-15.0%) compared to 11.6% (8.6-14.5%) in 229 glucose tolerant control subjects (NS). No difference in insulin secretion during an OGTT was seen between carriers of the different IVS6+26T-->C genotypes among the 229 middle-aged control subjects, nor among 302 glucose tolerant 60-year-old Danish Caucasians. Mutation analysis of the four exons comprising the DCoH gene revealed a previously described A-->G polymorphism located in the 3' untranslated region, which was not investigated further. In conclusion, mutations in HNF-1beta and DCoH are not a major cause of MODY or late onset type 2 diabetes in Danish Caucasian subjects.

Adult↗

Polymorphisms in the neurogenin 3 gene (NEUROG) and their relation to altered insulin secretion and diabetes in the Danish Caucasian population.

UNLABELLED: AIM/HYPOTHESIS. Neurogenin 3 (NEUROG3) is a member of the subfamily of basic-helix-loop-helix (bHLH) transcription factors involved in differentiation of the endocrine pancreas and therefore a possible candidate gene for maturity-onset diabetes of the young (MODY) and Type II (non-insulin-dependent) diabetes mellitus. METHODS: Using Polymerase-chain-reaction single-stranded-conformation polymorphism, we examined the coding region including the 5'-untranslated and 3'- untranslated regions of the NEUROG3 in a group of 133 diabetic patients comprising 19 MODY patients, 19 patients with dominant Type I diabetes, and 31 early-onset and 64 late-onset Type II diabetic patients. RESULTS: We found two missense mutations, Glyl67Arg and Serl99Phe, as well as two non-coding variants in the 5' UTR, a c --> t nucleotide variant at position -10 upstream of the start codon in one MODY patient and a 2 base pair (CA) deletion polymorphism at position -44/-45. Allele frequencies measured in 377 diabetic patients and in 217 glucose-tolerant control subjects were: Gly167Arg, 0.04 (95 % CI: 0.02-0.06) and 0.04 (0.02-0.06); Ser199Phe, 0.31 (0.26-0.36) and 0.30 (0.24-0.36); -44-45delCA, 0.33 (0.31-0.35) and 0.35 (0.32-0.38), respectively. Both Ser199Phe and the -44-45delCA were in linkage disequilibrium (chi2 > 60) but the Ser199Phe and the -44-45delCA polymorphism were not associated with consistent changes in fasting- or glucose-induced insulin secretion in 249 glucose-tolerant offspring (first-degree relatives) of Type II diabetic parents or in 217 unrelated middle-aged glucose tolerant subjects. CONCLUSION/INTERPRETATION: Genetic variability in NEUROG3 is not associated with dominant Type I diabetes, MODY, Type II diabetes or changes in insulin secretion in the Danish Caucasians examined subjects.

3' Untranslated Regions↗

Studies of variability in the PTEN gene among Danish caucasian patients with Type II diabetes mellitus.

AIM/HYPOTHESIS: Phosphatase and tensin homologue deleted from chromosome ten (PTEN) has recently been characterized as a novel member in the expanding network of proteins regulating the intracellular effects of insulin. By dephosphorylation of phosphatidyl-inositol-(3, 4, 5)-trisphosphate (PIP3) the PTEN protein regulates the insulin-dependent phosphoinositide 3-kinase (PI3K) signalling cassette and accordingly might function as a regulator of insulin sensitivity in skeletal muscle and adipose tissue. In this study we tested PTEN as a candidate gene for insulin resistance and late-onset Type II (non-insulin-dependent) diabetes mellitus in a Danish Caucasian population. METHODS: The nine exons of the PTEN, including intronic flanking regions were analysed by PCR-SSCP and heteroduplex analysis in 62 patients with insulin-resistant Type II diabetes. RESULTS: No mutations predicted to influence the expression or biological function of the PTEN protein but four intronic polymorphisms were identified: IVS1-96 A-->G (allelic frequency 0.22, 95 % CI: 0.12-0.32), IVS3 + 99 C-->T (0.01, CI: 0-0.03), IVS7-3 TT-->T (0.10, CI: 0.03-0.18) and IVS8 + 32 G-->T (0.35, CI: 0.23-0.47). The IVS8 + 32 G-->T polymorphism was used as a bi-allelic marker for the PTEN locus and examined in 379 patients with Type II diabetes and in 224 control subjects with normal glucose tolerance. The IVS8 + 32 G-->T polymorphism in the PTEN was not associated with Type II diabetes and it did not have any effect on body-mass index, blood pressure, HOMA insulin resistance index, or concentrations of plasma glucose, serum insulin or serum C peptide obtained during an oral glucose tolerance test (OGTT). CONCLUSION/INTERPRETATION: Variability in the PTEN is not a common cause of Type II diabetes in the Danish Caucasian population.

Adipose Tissue↗

Mutation analysis of peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) and relationships of identified amino acid polymorphisms to Type II diabetes mellitus.

AIM/HYPOTHESIS: This study aimed to investigate if variability in the peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC-1) gene is associated with Type II (non-insulin-dependent) diabetes mellitus. METHODS: The PGC-1 gene was examined in 53 Type II diabetic patients applying single strand conformational polymorphism analysis followed by nucleotide sequencing. Identified variants were genotyped in an association study comprising 483 Type II diabetic patients and 216 glucose-tolerant control subjects. A replication study was done in an additional 201 Type II diabetic patients and 293 glucose-tolerant subjects. Furthermore, a potential interaction between the Pro12Ala polymorphism of PPAR-gamma2 and the PGC-1 Gly482Ser variant on risk of Type II diabetes was investigated. RESULTS: A total of seven variants (Ser74Leu, IVS2 + 52C-->A, Thr394Thr, Asp475Asp, Gly482Ser, Thr528Thr, and Thr612Met) were identified and investigated in an association study. Six of the variants showed no association with Type II diabetes in the initial study. However, the Gly482Ser polymorphism, was more frequent among Type II diabetic patients (37.0 %) than among glucose-tolerant subjects (30.8 %) (p = 0.032). In a replication study the difference in allele frequencies of the Gly482Ser variant remained significant (p = 0.0135). The combined study yielded an allele frequency of 37.3 % (34.7-39.9) for Type II diabetic patients and 30.5 % (27.7-33.4) for glucose-tolerant subjects (p = 0.0007). No interaction between this variant and the Pro12Ala polymorphism of PPAR-gamma2 was observed. CONCLUSION/INTERPRETATION: A widespread Gly482Ser polymorphism of PGC-1 is associated with a 1.34 genotype relative risk of Type II diabetes.

Aged↗

Uncoupling proteins: functional characteristics and role in the pathogenesis of obesity and Type II diabetes.

Uncoupling proteins are mitochondrial carrier proteins which are able to dissipate the proton gradient of the inner mitochondrial membrane. This uncoupling process reduces the amount of ATP generated through an oxidation of fuels. The hypothesis that uncoupling proteins (UCPs) are candidate genes for human obesity or Type II (non-insulin-dependent) diabetes mellitus is based on the finding that a chemical uncoupling of the mitochondrial membrane reduces body adiposity, and that lower metabolic rates predict weight gain. It is straightforward to hypothesize that common polymorphisms of UCP1, UCP2 and UCP3 genes lower metabolic rate by a more efficient energy coupling in the mitochondria. Furthermore, genetically engineered mice over expressing different UCP homologues are lean and resistant to diet-induced obesity. The three uncoupling protein homologue genes UCP1, UCP2, and UCP3 have been investigated for polymorphisms and mutations and their impact on Type II diabetes mellitus, obesity, and body weight gain or BMI. The main conclusion is that variation in the UCP1, UCP2 or UCP3 genes is not associated with major alterations of body weight gain. The contribution of UCP genes towards polygenic obesity and Type II diabetes is evaluated and discussed.

Animals↗

Studies of the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-gamma2 (PPAR-gamma2) gene in relation to insulin sensitivity among glucose tolerant caucasians.

AIMS/HYPOTHESIS: We examined whether the Pro12-Ala polymorphism of the human peroxisome proliferator-activated receptor-gamma2 (PPAR-gamma2) gene was related to altered insulin sensitivity among glucose-tolerant subjects or a lower accumulated incidence or prevalence of IGT and Type II (non-insulin-dependent) diabetes mellitus among Scandinavian Caucasians. METHODS: The Pro12Ala polymorphism was examined using PCR-RFLP Whole-body insulin sensitivity measured under hyperinsulinaemic-euglycaemic conditions was estimated in a population-based sample of 616 glucose tolerant Swedish Caucasian men at age 70. In addition, insulin sensitivity index was measured using IVGTT and Bergman minimal modelling in a population-based sample of 364 young healthy Danish Caucasians. Finally, we evaluated whether the polymorphism predicted Type II diabetes and IGT in 841 seventy-year-old Swedish men. A case-control study was carried out in 654 unrelated Danish Type II diabetic patients and 742 Danish glucose tolerant subjects matched for age and sex. RESULTS: Whole-body insulin sensitivity was significantly improved in carriers compared with non-carriers of the Ala-allele of the codon 12 polymorphism in Swedish Caucasian men (6.0+/-2.5 vs 5.6+/-2.5 mg kg(-1) x min(-1) x mU/l](-1) x 100, p = 0.044). The same tendency, but not significant, was observed in the insulin sensitivity index among the group of young healthy Danish Caucasians. The incidence of Type II diabetes and IGT among the Swedish subjects at the age of 70 was similar in the three genotype-groups of the Pro12Ala variant and the Ala-allele was not related to a lower prevalence of Type II diabetes in Danish Caucasians. CONCLUSION/INTERPRETATION: The Ala-allele of the PPAR-gamma2 polymorphism is associated with improved whole body insulin sensitivity among Swedish Caucasians.

Aged↗

Genetic variability of the SUR1 promoter in relation to beta-cell function and Type II diabetes mellitus.

AIMS/HYPOTHESIS: We aimed to examine the promoter of SUR1 for genetic variation and to determine if variants were associated with Type II (non-insulin-dependent) diabetes mellitus or measures of beta-cell function. METHODS: We examined 465 bp upstream of the ATG site in 46 Type II diabetic patients and 15 glucose tolerant control subjects by SSCP-heteroduplex analysis. RESULTS: We identified an a --> t substitution 437 bp upstream of the ATG site. The allelic frequency was similar in 455 unrelated Type II diabetic patients and in 203 glucose tolerant control subjects matched for age (0.036, [95 % CI 0.019-0.053] vs 0.034 [95 % CI 0.009-0.059]; p = 0.92). Among the glucose tolerant subjects there were no differences between non-carriers (n = 189) and carriers (n = 14) of the variant in fasting values or 30 min values of plasma glucose and serum insulin during an oral glucose tolerance test. In a study of 233 glucose tolerant offspring of and spouses to Danish Caucasian Type II diabetic patients, non-carriers (n = 193) and carriers (n = 37) of the -437 a/t polymorphism did not differ in glucose or tolbutamide stimulated insulin response during an intravenous glucose tolerance test with intravenous tolbutamide injection [AUCs-insulin (0-8) min, 2290 +/- 1660 vs 2308 +/- 1935 pmol/l x min and AUCs-insulin(20-30 min), 3113 +/- 2033 vs. 3393 +/- 2830 pmol/l x min, respectively]. CONCLUSION/INTERPRETATION: We have identified a novel a/t polymorphism of the SUR1 gene promoter which is not associated with Type II diabetes mellitus or measures of beta-cell function. Previous reported non-functional variants of SUR1 associated with Type II diabetes mellitus still need to be accounted for.

ATP-Binding Cassette Transporters↗

The association between the val/ala-55 polymorphism of the uncoupling protein 2 gene and exercise efficiency.

BACKGROUND: Energy expenditure may partly be determined by genetic variations in uncoupling proteins. We have previously found an increased physical activity but a similar 24-h energy expenditure (EE) in subjects with the val/val-55 UCP2 genotype compared to those with the ala/ala genotype which indicates that the val-55 allele is statistically associated with a higher metabolic efficiency. DESIGN: EE during bicycling was determined by indirect calorimetry at three different loads (30, 40 and 60% of VO2max in eight subjects with the val/val-55 genotype (35+/-6 y weight=76.8+/-13.6 kg, VO2max=2.79+/-0.71 l/min) and eight subjects with the ala/ala-55 genotype (37+/-3 y, weight=78.3+/-16.5 kg, VO2max=2.66+/-0.41 l/min). RESULTS: Incremental exercise efficiency across the three different work levels was higher in the val/val (25.3%, c.i. 24.2-26.4%) than in the ala/ala (23.6%, c.i. 22.5-24.7%) genotype P<0.05. Gross exercise efficiency at 40% VO2max was higher in the val/val (15.3+/-0.6%) than in the ala/ala (13.5+/-0.4%) group. CONCLUSION: As the val/ala-55 polymorphism is located in a domain of the protein without any known function, the different exercise efficiency between the two genotypes most likely reflects a linkage disequilibrium with a functionally significant polymorphism in UCP2 or in the neighbouring UCP3 gene. The study suggests that variations in the UCP genes may affect not only basal metabolic rate but also influence energy costs of exercise.

Adult↗

The Asn363Ser variant of the glucocorticoid receptor gene is not associated with obesity or weight gain in Danish men.

OBJECTIVE: Testing association of the Asn363Ser variant of the glucocorticoid gene with measures of obesity and weight gain. SUBJECTS: 741 obese subjects (BMI > or = 31 kg/m(2) at selection) and 854 random control subjects from the same population, examined at draft board examination and after on average 27.4+/- y. A lean control group (n=351) was further selected as the fraction from the cohort group having a BMI below 25.0 kg/m(2) at the latest examination. METHODS: Using PCR-RFLP subjects were genotyped for the Asn363Ser variant and grouped according to genotype. RESULTS: The prevalence of the Ser363 allele was 4.7% (95% Cl: 3.3-6.2%) among the obese, 4.1% (2.7-5.5%) among the random cohort subjects and 4.3% (2.1-6.5%) among lean control subjects, respectively, showing no significant differences between the groups (P > 0.1). Furthermore, no differences in BMI, waist-hip ratio or weight gain were seen within any of the groups when defined according to the glucocorticoid receptor genotype. CONCLUSION: In the examined population this marker is not a relevant predictor of obesity.

Adult↗