| 1. |
- Flannick, Jason, et al.
(författare)
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Data Descriptor : Sequence data and association statistics from 12,940 type 2 diabetes cases and controls
- 2017
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Ingår i: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (> 80% of low-frequency coding variants in similar to ~82 K Europeans via the exome chip, and similar to ~90% of low-frequency non-coding variants in similar to ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D.
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| 2. |
- Fuchsberger, Christian, et al.
(författare)
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The genetic architecture of type 2 diabetes
- 2016
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 536:7614, s. 41-47
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Tidskriftsartikel (refereegranskat)abstract
- The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of the heritability of this disease. Here, to test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole-genome sequencing in 2,657 European individuals with and without diabetes, and exome sequencing in 12,940 individuals from five ancestry groups. To increase statistical power, we expanded the sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support the idea that lower-frequency variants have a major role in predisposition to type 2 diabetes.
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| 3. |
- Manning, Alisa, et al.
(författare)
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A Low-Frequency Inactivating AKT2 Variant Enriched in the Finnish Population Is Associated With Fasting Insulin Levels and Type 2 Diabetes Risk
- 2017
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Ingår i: Diabetes. - : AMER DIABETES ASSOC. - 0012-1797 .- 1939-327X. ; 66:7, s. 2019-2032
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Tidskriftsartikel (refereegranskat)abstract
- To identify novel coding association signals and facilitate characterization of mechanisms influencing glycemic traits and type 2 diabetes risk, we analyzed 109,215 variants derived from exome array genotyping together with an additional 390,225 variants from exome sequence in up to 39,339 normoglycemic individuals from five ancestry groups. We identified a novel association between the coding variant (p.Pro50Thr) in AKT2 and fasting plasma insulin (FI), a gene in which rare fully penetrant mutations are causal for monogenic glycemic disorders. The low-frequency allele is associated with a 12% increase in FI levels. This variant is present at 1.1% frequency in Finns but virtually absent in individuals from other ancestries. Carriers of the FI-increasing allele had increased 2-h insulin values, decreased insulin sensitivity, and increased risk of type 2 diabetes (odds ratio 1.05). In cellular studies, the AKT2-Thr50 protein exhibited a partial loss of function. We extend the allelic spectrum for coding variants in AKT2 associated with disorders of glucose homeostasis and demonstrate bidirectional effects of variants within the pleckstrin homology domain of AKT2.
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| 4. |
- Ikram, M. Arfan, et al.
(författare)
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Common variants at 6q22 and 17q21 are associated with intracranial volume
- 2012
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 44:5, s. 539-544
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Tidskriftsartikel (refereegranskat)abstract
- During aging, intracranial volume remains unchanged and represents maximally attained brain size, while various interacting biological phenomena lead to brain volume loss. Consequently, intracranial volume and brain volume in late life reflect different genetic influences. Our genome-wide association study (GWAS) in 8,175 community-dwelling elderly persons did not reveal any associations at genome-wide significance (P < 5 x 10(-8)) for brain volume. In contrast, intracranial volume was significantly associated with two loci: rs4273712 (P = 3.4 x 10(-11)), a known height-associated locus on chromosome 6q22, and rs9915547 (P = 1.5 x 10(-12)), localized to the inversion on chromosome 17q21. We replicated the associations of these loci with intracranial volume in a separate sample of 1,752 elderly persons (P = 1.1 x 10(-3) for 6q22 and 1.2 x 10(-3) for 17q21). Furthermore, we also found suggestive associations of the 17q21 locus with head circumference in 10,768 children (mean age of 14.5 months). Our data identify two loci associated with head size, with the inversion at 17q21 also likely to be involved in attaining maximal brain size.
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| 5. |
- Lindgren, Hanna, et al.
(författare)
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Putaminal Upregulation of FosB/Delta FosB-Like Immunoreactivity in Parkinson's Disease Patients with Dyskinesia
- 2011
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Ingår i: Journal of Parkinson's Disease. - 1877-718X. ; 1:4, s. 347-357
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Tidskriftsartikel (refereegranskat)abstract
- The transcription factor Delta FosB is a mediator of maladaptive neuroplasticity in animal models of Parkinson's disease (PD) and L-DOPA-induced dyskinesia. Using an antibody that recognizes all known isoforms of FosB and Delta FosB, we have examined the expression of these proteins in post-mortem basal ganglia sections from PD patients. The patient cases were classified as being dyskinetic or non-dyskinetic based on their clinical records. Sections from neurologically healthy controls were also included in the study. Compared to both controls and non-dyskinetic cases, the dyskinetic group showed a higher density of FosB/Delta FosB-immunopositive cells in the posterior putamen, which represents the motor region of the striatum in primates. In contrast, the number of FosB/Delta FosB-positive cells did not differ significantly among the groups in the caudate, a region primarily involved with the processing of cognitive and limbic-related information. Only sparse FosB/Delta FosB immunoreactivity was found in the in the pallidum externum and internum, and no significant group differences were detected in these nuclei. The putaminal elevation of FosB/Delta FosB-like immunoreactivity in patients who had been affected by L-DOPA-induced dyskinesia is consistent with results from both rat and non-human primate models of this movement disorder. The present findings support the hypothesis of an involvement of Delta FosB-related transcription factors in the molecular mechanisms of L-DOPA-induced dyskinesia.
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| 6. |
- Lindgren, Hanna S., et al.
(författare)
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Putaminal Upregulation of FosB/ΔFosB-Like Immunoreactivity in Parkinson's Disease Patients with Dyskinesia
- 2011
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Ingår i: Journal of Parkinson's Disease. - : IOS Press. - 1877-7171 .- 1877-718X. ; 1:4, s. 347-357
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Tidskriftsartikel (refereegranskat)abstract
- The transcription factor FosB is a mediator of maladaptive neuroplasticity in animal models of Parkinson´s disease (PD) and L-DOPA-induced dyskinesia. Using an antibody that recognizes all known isoforms of FosB and FosB, we have examined the expression of these proteins in post-mortem basal ganglia sections from PD patients. The patient cases were classified as being dyskinetic or non-dyskinetic based on their clinical records. Sections from neurologically healthy controls were also included in the study. Compared to both controls and non-dyskinetic cases, the dyskinetic group showed a higher density of FosB/ FosB-immunopositive cells in the posterior putamen, which represents the motor region of the striatum in primates. In contrast, the number of FosB/ FosB-positive cells did not differ significantly among the groups in the caudate, a region primarily involved with the processing of cognitive and limbic-related information. Only sparse FosB/ FosB immunoreactivity was found in the in the pallidum externum and internum, and no significant group differences were detected in these nuclei. The putaminal elevation of FosB/ FosB-like immunoreactivity in patients who had been affected by L-DOPA-induced dyskinesia is consistent with results from both rat and non-human primate models of this movement disorder. The present findings support the hypothesis of an involvement of FosB-related transcription factors in the molecular mechanisms of L-DOPA-induced dyskinesia.
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| 7. |
- Taal, H. Rob, et al.
(författare)
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Common variants at 12q15 and 12q24 are associated with infant head circumference
- 2012
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 44:5, s. 532-538
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Tidskriftsartikel (refereegranskat)abstract
- To identify genetic variants associated with head circumference in infancy, we performed a meta-analysis of seven genome-wide association studies (GWAS) (N = 10,768 individuals of European ancestry enrolled in pregnancy and/or birth cohorts) and followed up three lead signals in six replication studies (combined N = 19,089). rs7980687 on chromosome 12q24 (P = 8.1 x 10(-9)) and rs1042725 on chromosome 12q15 (P = 2.8 x 10(-10)) were robustly associated with head circumference in infancy. Although these loci have previously been associated with adult height(1), their effects on infant head circumference were largely independent of height (P = 3.8 x 10(-7) for rs7980687 and P = 1.3 x 10(-7) for rs1042725 after adjustment for infant height). A third signal, rs11655470 on chromosome 17q21, showed suggestive evidence of association with head circumference (P = 3.9 x 10(-6)). SNPs correlated to the 17q21 signal have shown genome-wide association with adult intracranial volume(2), Parkinson's disease and other neurodegenerative diseases(3-5), indicating that a common genetic variant in this region might link early brain growth with neurological disease in later life.
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| 8. |
- Francardo, Veronica, et al.
(författare)
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Chapter 22 - Rodent Models of Treatment-Related Complications in Parkinson Disease
- 2014. - 2nd
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Ingår i: Movement Disorders : Genetics and Models - Genetics and Models. - 9780124051959 ; , s. 373-386
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Bokkapitel (refereegranskat)abstract
- Dopamine replacement therapy effectively relieves the typical motor features of Parkinson disease (PD), but it can cause complications that limit its utility. Dyskinesia (abnormal involuntary movements) and motor fluctuations (abrupt changes in the patients' motor status) occur in most PD patients after a few years of 3,4-dihydroxyphenyl-. l-alanine (l-DOPA) pharmacotherapy. Animal models reproducing these motor complications can be obtained in mice and rats if the nigrostriatal dopamine pathway is severely damaged. Within the large arsenal of neurotoxic and genetic models of PD, rodents with unilateral 6-hydroxydopamine lesions have the best characteristics for the sake of modeling l-DOPA-induced dyskinesia. When treated chronically with high doses of l-DOPA, these rodent models may also display motor response alterations reminiscent of the wearing-off fluctuations that occur in PD patients. Because of research performed on these animal models, our understanding of the molecular and biochemical mechanisms of l-DOPA-induced dyskinesia has made great advances, and several pharmacological approaches to treatment have been recently identified and successfully tested in proof-of-concept trials in PD patients. It is now well recognized that dopaminergic therapies for PD also cause nonmotor fluctuations (e.g., abrupt changes in mood and cognitive performance) and impulse control disorders. Valid rodent models of these nonmotor complications need to be developed as an important tool for basic and translational research on the cognitive and psychiatric features of PD.
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| 9. |
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| 10. |
- Ohlin, Elisabet, et al.
(författare)
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Vascular endothelial growth factor is upregulated by L-dopa in the parkinsonian brain: implications for the development of dyskinesia.
- 2011
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Ingår i: Brain. - : Oxford University Press (OUP). - 1460-2156 .- 0006-8950. ; 134, s. 2339-2357
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Tidskriftsartikel (refereegranskat)abstract
- Angiogenesis and increased permeability of the blood-brain barrier have been reported to occur in animal models of Parkinson's disease and l-dopa-induced dyskinesia, but the significance of these phenomena has remained unclear. Using a validated rat model of l-dopa-induced dyskinesia, this study demonstrates that chronic treatment with l-dopa dose dependently induces the expression of vascular endothelial growth factor in the basal ganglia nuclei. Vascular endothelial growth factor was abundantly expressed in astrocytes and astrocytic processes in the proximity of blood vessels. When co-administered with l-dopa, a small molecule inhibitor of vascular endothelial growth factor signalling significantly attenuated the development of dyskinesia and completely blocked the angiogenic response and associated increase in blood-brain barrier permeability induced by the treatment. The occurrence of angiogenesis and vascular endothelial growth factor upregulation was verified in post-mortem basal ganglia tissue from patients with Parkinson's disease with a history of dyskinesia, who exhibited increased microvascular density, microvascular nestin expression and an upregulation of vascular endothelial growth factor messenger ribonucleic acid. These congruent findings in the rat model and human patients indicate that vascular endothelial growth factor is implicated in the pathophysiology of l-dopa-induced dyskinesia and emphasize an involvement of the microvascular compartment in the adverse effects of l-dopa pharmacotherapy in Parkinson's disease.
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