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- Boesgaard, T. W., et al.
(författare)
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Variant near ADAMTS9 known to associate with type 2 diabetes is related to insulin resistance in offspring of type 2 diabetes patients--EUGENE2 study
- 2009
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Ingår i: PLoS One. - 1932-6203. ; 4:9
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Tidskriftsartikel (refereegranskat)abstract
- BACKROUND: A meta-analysis combining results from three genome-wide association studies and followed by large-scale replication identified six novel type 2 diabetes loci. Subsequent studies of the effect of these variants on estimates of the beta-cell function and insulin sensitivity have been inconclusive. We examined these variants located in or near the JAZF1 (rs864745), THADA (rs7578597), TSPAN8 (rs7961581), ADAMTS9 (rs4607103), NOTCH2 (rs10923931) and the CDC123/CAMK1D (rs12779790) genes for associations with measures of pancreatic beta-cell function and insulin sensitivity. METHODOLOGY/RESULTS: Oral and intravenous glucose stimulated insulin release (n = 849) and insulin sensitivity (n = 596) estimated from a hyperinsulinemic euglycemic clamp were measured in non-diabetic offspring of type 2 diabetic patients from five European populations. Assuming an additive genetic model the diabetes-associated major C-allele of rs4607103 near ADAMTS9 associated with reduced insulin-stimulated glucose uptake (p = 0.002) during a hyperinsulinemic euglycemic clamp. However, following intravenous and oral administration of glucose serum insulin release was increased in individuals with the C-allele (p = 0.003 and p = 0.01, respectively). A meta-analyse combining clamp and IVGTT data from a total of 905 non-diabetic individuals showed that the C-risk allele associated with decreased insulin sensitivity (p = 0.003) and increased insulin release (p = 0.002). The major T-allele of the intronic JAZF1 rs864745 conferring increased diabetes risk was associated with increased 2(nd) phase serum insulin release during an IVGTT (p = 0.03), and an increased fasting serum insulin level (p = 0.001). The remaining variants did not show any associations with insulin response, insulin sensitivity or any other measured quantitative traits. CONCLUSION: The present studies suggest that the diabetogenic impact of the C-allele of rs4607103 near ADAMTS9 may in part be mediated through decreased insulin sensitivity of peripheral tissues.
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| 2. |
- Staiger, H., et al.
(författare)
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A candidate type 2 diabetes polymorphism near the HHEX locus affects acute glucose-stimulated insulin release in European populations: results from the EUGENE2 study
- 2008
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Ingår i: Diabetes. - 1939-327X. ; 57:2, s. 514-7
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: In recent genome-wide association studies, two single nucleotide polymorphisms (SNPs) near the HHEX locus were shown to be more frequent in type 2 diabetic patients than in control subjects. Based on HHEX's function during embryonic development of the ventral pancreas in mice, we investigated whether these SNPs affect beta-cell function in humans. RESEARCH DESIGN AND METHODS: A total of 854 nondiabetic subjects, collected from five European clinical centers, were genotyped for the HHEX SNPs rs1111875 and rs7923837 and thoroughly characterized by an oral glucose tolerance test (OGTT). To assess glucose-stimulated insulin release, a subgroup of 758 subjects underwent an intravenous glucose tolerance test (IVGTT). RESULTS: SNPs rs1111875 and rs7923837 were not associated with anthropometric data (age, weight, height, BMI, body fat, and waist and hip circumference). After adjustment for center, family relationship, sex, age, and BMI, both SNPs were also not associated with glucose and insulin concentrations in the fasting state and during the OGTT or with measures of insulin sensitivity. Furthermore, HHEX SNP rs1111875 was not associated with insulin release during the IVGTT. By contrast, the minor A-allele of HHEX SNP rs7923837 was significantly associated with higher IVGTT-derived first-phase insulin release before and after appropriate adjustment (P = 0.013 and P = 0.014, respectively). CONCLUSIONS: A common genetic variation in the 3'-flanking region of the HHEX locus, i.e., SNP rs7923837, is associated with altered glucose-stimulated insulin release. This SNP's major allele represents a risk allele for beta-cell dysfunction and, thus, might confer increased susceptibility of beta-cells toward adverse environmental factors.
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