| 21. |
- Miguel-Escalada, Irene, et al.
(författare)
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Human pancreatic islet three-dimensional chromatin architecture provides insights into the genetics of type 2 diabetes
- 2019
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 51:7, s. 1137-1148
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Tidskriftsartikel (refereegranskat)abstract
- Genetic studies promise to provide insight into the molecular mechanisms underlying type 2 diabetes (T2D). Variants associated with T2D are often located in tissue-specific enhancer clusters or super-enhancers. So far, such domains have been defined through clustering of enhancers in linear genome maps rather than in three-dimensional (3D) space. Furthermore, their target genes are often unknown. We have created promoter capture Hi-C maps in human pancreatic islets. This linked diabetes-associated enhancers to their target genes, often located hundreds of kilobases away. It also revealed >1,300 groups of islet enhancers, super-enhancers and active promoters that form 3D hubs, some of which show coordinated glucose-dependent activity. We demonstrate that genetic variation in hubs impacts insulin secretion heritability, and show that hub annotations can be used for polygenic scores that predict T2D risk driven by islet regulatory variants. Human islet 3D chromatin architecture, therefore, provides a framework for interpretation of T2D genome-wide association study (GWAS) signals.
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| 22. |
- Banasik, Karina, et al.
(författare)
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The FOXO3A rs2802292 G-Allele Associates with Improved Peripheral and Hepatic Insulin Sensitivity and Increased Skeletal Muscle-FOXO3A mRNA Expression in Twins.
- 2011
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Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 1945-7197 .- 0021-972X. ; 96, s. 119-124
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The minor G allele of FOXO3A rs2802292 has been associated with longevity. We aimed to investigate whether a phenotype related to healthy metabolic aging could be identified in individuals carrying the longevity-associated FOXO3A rs2802292 G allele. Research Design and Methods: rs2802292 was genotyped in a phenotypically well-characterized population of young and elderly twins (n = 190) and in the population-based Inter99 cohort (n = 5768). All participants underwent oral glucose tolerance tests, and the twin population was additionally examined with an iv glucose tolerance test and a hyperinsulinemic, euglycemic clamp. Basal and insulin-stimulated FOXO3A mRNA expression was assessed in skeletal muscle biopsies from the twin population. Results: In the twin sample, carriers of the minor G allele of rs2802292 showed reduced fasting plasma insulin [per allele effect (β) = -13% (-24; -1) (95% confidence interval), P = 0.03] and lower incremental area under the curve 0-120 min for insulin after an oral glucose load [β = -14% (-23; -), P = 0.005]. The G allele was associated with increased peripheral insulin action [glucose disposal rate clamp, β = 0.85 mg·kgfat-free mass(-1) · min(-1) (0.049; 1.64), P = 0.04] and lower hepatic insulin resistance index [β = -13% (-25; -1), P = 0.03]. Furthermore, carriers of the G allele had increased basal FOXO3A mRNA expression in skeletal muscle compared with T-allele carriers [β = 16% (0; 33), P = 0.047]. In the Inter99 sample, we found an association with reduced incremental area under the curve 0-120 min for insulin after an oral glucose load [β = -3% (-5; -0.07), P = 0.04], but this association was not significant after adjustment for body mass index. Conclusion: Our data indicate that the minor G allele of FOXO3A rs2802292 is associated with enhanced peripheral and hepatic insulin sensitivity in our small twin cohort, which may be mediated through increased FOXO3A mRNA expression, although no major metabolic impact of rs2802292 was found in the large Inter99 cohort.
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| 23. |
- Bernatsky, Sasha, et al.
(författare)
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Cancer risk in systemic lupus: An updated international multi-centre cohort study
- 2013
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Ingår i: Journal of Autoimmunity. - : Elsevier BV. - 0896-8411. ; 42, s. 130-135
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To update estimates of cancer risk in SLE relative to the general population. Methods: A multisite international SLE cohort was linked with regional tumor registries. Standardized incidence ratios (SIRs) were calculated as the ratio of observed to expected cancers. Results: Across 30 centres, 16,409 patients were observed for 121,283 (average 7.4) person years. In total, 644 cancers occurred. Some cancers, notably hematologic malignancies, were substantially increased (SIR 3.02, 95% confidence interval, CI, 2.48, 3.63), particularly non-Hodgkin's lymphoma, NHL (SIR 4.39, 95% CI 3.46, 5.49) and leukemia. In addition, increased risks of cancer of the vulva (SIR 3.78, 95% CI 1.52, 7.78), lung (SIR 1.30, 95% CI 1.04, 1.60), thyroid (SIR 1.76, 95% CI 1.13, 2.61) and possibly liver (SIR 1.87, 95% CI 0.97, 3.27) were suggested. However, a decreased risk was estimated for breast (SIR 0.73, 95% CI 0.61-0.88), endometrial (SIR 0.44, 95% CI 0.23-0.77), and possibly ovarian cancers (0.64, 95% Cl 0.34-1.10). The variability of comparative rates across different cancers meant that only a small increased risk was estimated across all cancers (SIR 1.14, 95% CI 1.05, 1.23). Conclusion: These data estimate only a small increased risk in SLE (versus the general population) for cancer over-all. However, there is clearly an increased risk of NHL and cancers of the vulva, lung, thyroid, and possibly liver. It remains unclear to what extent the association with NHL is mediated by innate versus exogenous factors. Similarly, the etiology of the decreased breast, endometrial, and possibly ovarian cancer risk is uncertain, though investigations are ongoing. (C) 2013 Elsevier Ltd. All rights reserved.
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| 24. |
- Bernatsky, Sasha, et al.
(författare)
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Lymphoma risk in systemic lupus: effects of disease activity versus treatment
- 2014
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 73:1, s. 138-142
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Tidskriftsartikel (refereegranskat)abstract
- Objective To examine disease activity versus treatment as lymphoma risk factors in systemic lupus erythematosus (SLE). Methods We performed case-cohort analyses within a multisite SLE cohort. Cancers were ascertained by regional registry linkages. Adjusted HRs for lymphoma were generated in regression models, for time-dependent exposures to immunomodulators (cyclophosphamide, azathioprine, methotrexate, mycophenolate, antimalarial drugs, glucocorticoids) demographics, calendar year, Sjogren's syndrome, SLE duration and disease activity. We used adjusted mean SLE Disease Activity Index scores (SLEDAI-2K) over time, and drugs were treated both categorically (ever/never) and as estimated cumulative doses. Results We studied 75 patients with lymphoma (72 non-Hodgkin, three Hodgkin) and 4961 cancer-free controls. Most lymphomas were of B-cell origin. As is seen in the general population, lymphoma risk in SLE was higher in male than female patients and increased with age. Lymphomas occurred a mean of 12.4years (median 10.9) after SLE diagnosis. Unadjusted and adjusted analyses failed to show a clear association of disease activity with lymphoma risk. There was a suggestion of greater exposure to cyclophosphamide and to higher cumulative steroids in lymphoma cases than the cancer-free controls. Conclusions In this large SLE sample, there was a suggestion of higher lymphoma risk with exposure to cyclophosphamide and high cumulative steroids. Disease activity itself was not clearly associated with lymphoma risk. Further work will focus on genetic profiles that might interact with medication exposure to influence lymphoma risk in SLE.
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| 25. |
- Færch, Kristine, et al.
(författare)
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Insulin resistance is accompanied by increased fasting glucagon and delayed glucagon suppression in individuals with normal and impaired glucose regulation
- 2016
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 65:11, s. 3473-3481
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Tidskriftsartikel (refereegranskat)abstract
- Hyperinsulinemia is an adaptive mechanism that enables the maintenance of normoglycemia in the presence of insulin resistance. We assessed whether glucagon is also involved in the adaptation to insulin resistance. A total of 1,437 individuals underwent an oral glucose tolerance test with measurements of circulating glucose, insulin, and glucagon concentrations at 0, 30 and 120 min. Early glucagon suppression was defined as suppression in the period from 0 to 30 min, and late glucagon suppression as 30 to 120 min after glucose intake. Insulin sensitivity was estimated by the validated insulin sensitivity index. Individuals with screen-detected diabetes had 30% higher fasting glucagon levels and diminished early glucagon suppression, but greater late glucagon suppression when compared with individuals with normal glucose tolerance (P 0.014). Higher insulin resistance was associated with higher fasting glucagon levels, less early glucagon suppression, and greater late glucagon suppression (P < 0.001). The relationship between insulin sensitivity and fasting glucagon concentrations was nonlinear (P < 0.001). In conclusion, increased fasting glucagon levels and delayed glucagon suppression, together with increased circulating insulin levels, develop in parallel with insulin resistance. Therefore, glucose maintenance during insulin resistance may depend not only on hyperinsulinemia but also on the ability to suppress glucagon early after glucose intake.
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| 26. |
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| 27. |
- Harris, Valerie M., et al.
(författare)
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Klinefelters syndrome (47,XXY) is in excess among men with Sjogrens syndrome
- 2016
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Ingår i: Clinical Immunology. - : ACADEMIC PRESS INC ELSEVIER SCIENCE. - 1521-6616 .- 1521-7035. ; 168, s. 25-29
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Tidskriftsartikel (refereegranskat)abstract
- Primary Sjogrens syndrome (pSS) has a strong female bias. We evaluated an X chromosome dose effect by analyzing 47,XXY (Klinefelters syndrome, 1 in 500 live male births) among subjects with pSS. 47,XXY was determined by examination of fluorescence intensity of single nucleotide polymorphisms from the X and Y chromosomes. Among 136 pSS men there were 4 with 47,XXY. This was significantly different from healthy controls (1 of 1254 had 47)0(Y, p = 0.0012 by Fishers exact test) as well men with rheumatoid arthritis (0 of 363 with 47,XXY), but not different compared to men with systemic lupus erythematosus (SLE) (4 of 136 versus 8 of 306, Fishers exact test p = NS). These results are consistent with the hypothesis that the number of X chromosomes is critical for the female bias of pSS, a property that may be shared with SLE but not RA. Published by Elsevier Inc.
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| 28. |
- Li, He, et al.
(författare)
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Identification of a Sjögren's syndrome susceptibility locus at OAS1 that influences isoform switching, protein expression, and responsiveness to type I interferons
- 2017
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Ingår i: PLOS Genetics. - : PUBLIC LIBRARY SCIENCE. - 1553-7390 .- 1553-7404. ; 13:6
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Tidskriftsartikel (refereegranskat)abstract
- Sjogren's syndrome (SS) is a common, autoimmune exocrinopathy distinguished by keratoconjunctivitis sicca and xerostomia. Patients frequently develop serious complications including lymphoma, pulmonary dysfunction, neuropathy, vasculitis, and debilitating fatigue. Dysregulation of type I interferon (IFN) pathway is a prominent feature of SS and is correlated with increased autoantibody titers and disease severity. To identify genetic determinants of IFN pathway dysregulation in SS, we performed cis-expression quantitative trait locus (eQTL) analyses focusing on differentially expressed type I IFN-inducible transcripts identified through a transcriptome profiling study. Multiple cis-eQTLs were associated with transcript levels of 2'-5'-oligoadenylate synthetase 1 (OAS1) peaking at rs10774671 (PeQTL = 6.05 x 10(-14)). Association of rs10774671 with SS susceptibility was identified and confirmed through meta-analysis of two independent cohorts (P-meta = 2.59 x 10(-9); odds ratio = 0.75; 95% confidence interval = 0.66-0.86). The risk allele of rs10774671 shifts splicing of OAS1 from production of the p46 isoform to multiple alternative transcripts, including p42, p48, and p44. We found that the isoforms were differentially expressed within each genotype in controls and patients with and without autoantibodies. Furthermore, our results showed that the three alternatively spliced isoforms lacked translational response to type I IFN stimulation. The p48 and p44 isoforms also had impaired protein expression governed by the 3' end of the transcripts. The SS risk allele of rs10774671 has been shown by others to be associated with reduced OAS1 enzymatic activity and ability to clear viral infections, as well as reduced responsiveness to IFN treatment. Our results establish OAS1 as a risk locus for SS and support a potential role for defective viral clearance due to altered IFN response as a genetic pathophysiological basis of this complex autoimmune disease.
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| 29. |
- Liu, Ke, et al.
(författare)
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X Chromosome Dose and Sex Bias in Autoimmune Diseases
- 2016
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Ingår i: Arthritis & Rheumatology. - : WILEY-BLACKWELL. - 2326-5191 .- 2326-5205. ; 68:5, s. 1290-1300
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Tidskriftsartikel (refereegranskat)abstract
- Objective. More than 80% of autoimmune disease predominantly affects females, but the mechanism for this female bias is poorly understood. We suspected that an X chromosome dose effect accounts for this, and we undertook this study to test our hypothesis that trisomy X (47, XXX; occurring in similar to 1 in 1,000 live female births) would be increased in patients with female-predominant diseases (systemic lupus erythematosus [SLE], primary Sjogrens syndrome [SS], primary biliary cirrhosis, and rheumatoid arthritis [RA]) compared to patients with diseases without female predominance (sarcoidosis) and compared to controls. Methods. All subjects in this study were female. We identified subjects with 47, XXX using aggregate data from single-nucleotide polymorphism arrays, and, when possible, we confirmed the presence of 47, XXX using fluorescence in situ hybridization or quantitative polymerase chain reaction. Results. We found 47, XXX in 7 of 2,826 SLE patients and in 3 of 1,033 SS patients, but in only 2 of 7,074 controls (odds ratio in the SLE and primary SS groups 8.78 [95% confidence interval 1.67-86.79], P = 0.003 and odds ratio 10.29 [95% confidence interval 1.18-123.47], P = 0.02, respectively). One in 404 women with SLE and 1 in 344 women with SS had 47, XXX. There was an excess of 47, XXX among SLE and SS patients. Conclusion. The estimated prevalence of SLE and SS in women with 47, XXX was similar to 2.5 and similar to 2.9 times higher, respectively, than that in women with 46, XX and similar to 25 and similar to 41 times higher, respectively, than that in men with 46, XY. No statistically significant increase of 47, XXX was observed in other female-biased diseases (primary biliary cirrhosis or RA), supporting the idea of multiple pathways to sex bias in autoimmunity.
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| 30. |
- Liu, Ke, et al.
(författare)
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X Chromosome Dose and Sex Bias in Autoimmune Diseases : Increased 47,XXX in Systemic Lupus Erythematosus and Sjögren's Syndrome
- 2016
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Ingår i: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 68:5, s. 1290-1300
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:More than 80% of autoimmune disease is female dominant, but the mechanism for this female bias is poorly understood. We suspected an X chromosome dose effect and hypothesized that trisomy X (47,XXX, 1 in ∼1,000 live female births) would be increased in female predominant diseases (e.g. systemic lupus erythematosus [SLE], primary Sjögren's syndrome [SS], primary biliary cirrhosis [PBC] and rheumatoid arthritis [RA]) compared to diseases without female predominance (sarcoidosis) and controls.METHODS:We identified 47,XXX subjects using aggregate data from single nucleotide polymorphism (SNP) arrays and confirmed, when possible, by fluorescent in situ hybridization (FISH) or quantitative polymerase chain reaction (q-PCR).RESULTS:We found 47,XXX in seven of 2,826 SLE and three of 1,033 SS female patients, but only in two of the 7,074 female controls (p=0.003, OR=8.78, 95% CI: 1.67-86.79 and p=0.02, OR=10.29, 95% CI: 1.18-123.47; respectively). One 47,XXX subject was present for ∼404 SLE women and ∼344 SS women. 47,XXX was present in excess among SLE and SS subjects.CONCLUSION:The estimated prevalence of SLE and SS in women with 47,XXX was respectively ∼2.5 and ∼2.9 times higher than in 46,XX women and ∼25 and ∼41 times higher than in 46,XY men. No statistically significant increase of 47,XXX was observed in other female-biased diseases (PBC or RA), supporting the idea of multiple pathways to sex bias in autoimmunity. This article is protected by copyright. All rights reserved.
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