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- Knevel, Rachel, et al.
(författare)
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A genetic variant in osteoprotegerin is associated with progression of joint destruction in rheumatoid arthritis
- 2014
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Ingår i: Arthritis Research and Therapy. - : Springer Science and Business Media LLC. - 1478-6362 .- 1478-6354. ; 16:3
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Progression of joint destruction in rheumatoid arthritis (RA) is partly heritably; 45 to 58% of the variance in joint destruction is estimated to be explained by genetic factors. The binding of RANKL (Receptor Activator for Nuclear Factor kappa B Ligand) to RANK results in the activation of TRAF6 (tumor necrosis factor (TNF) receptor associated factor-6), and osteoclast formation ultimately leading to enhanced bone resorption. This bone resorption is inhibited by osteoprotegerin (OPG) which prevents RANKL-RANK interactions. The OPG/RANK/RANKL/TRAF6 pathway plays an important role in bone remodeling. Therefore, we investigated whether genetic variants in OPG, RANK, RANKL and TRAF6 are associated with the rate of joint destruction in RA. Methods: 1,418 patients with 4,885 X-rays of hands and feet derived from four independent data-sets were studied. In each data-set the relative increase of the progression rate per year in the presence of a genotype was assessed. First, explorative analyses were performed on 600 RA-patients from Leiden. 109 SNPs, tagging OPG, RANK, RANKL and TRAF6, were tested. Single nucleotide polymorphisms (SNPs) significantly associated in phase-1 were genotyped in data-sets from Groningen (Netherlands), Sheffield (United Kingdom) and Lund (Switzerland). Data were summarized in an inverse weighted variance meta-analysis. Bonferonni correction for multiple testing was applied. Results: We found that 33 SNPs were significantly associated with the rate of joint destruction in phase-1. In phase-2, six SNPs in OPG and four SNPs in RANK were associated with progression of joint destruction with P-value <0.05. In the meta-analyses of all four data-sets, RA-patients with the minor allele of OPG-rs1485305 expressed higher rates of joint destruction compared to patients without these risk variants (P = 2.35x10(-4)). This variant was also significant after Bonferroni correction. Conclusions: These results indicate that a genetic variant in OPG is associated with a more severe rate of joint destruction in RA.
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| 2. |
- Lopez-Isac, Elena, et al.
(författare)
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Identification of IL12RB1 as a novel systemic sclerosis susceptibility locus
- 2014
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Ingår i: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 66:12, s. 3521-3523
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- ObjectiveLumbar spinal stenosis is one of the most commonly diagnosed spinal disorders in older adults. Although the pathophysiology of the clinical syndrome is not well understood, a narrow central canal or intervertebral foramen is an essential or defining feature. The aim of the present study was to estimate the magnitude of genetic versus environmental influences on central lumbar spinal stenosis and to investigate disc degeneration and stature or bone development as possible genetic pathways. MethodsA classic twin study with multivariate analyses considering lumbar level and other covariates was conducted. The study sample comprised 598 male twins (147 monozygotic and 152 dizygotic pairs), 35-70 years of age, from the population-based Finnish Twin Cohort. The primary phenotypes were central lumbar stenosis as assessed qualitatively on magnetic resonance imaging (MRI) and quantitatively measured dural sac cross-sectional area. Additional phenotypes (to examine possible genetic pathways) included disc bulging and standing height, as an indicator of overall skeletal size or development. ResultsThe heritability estimate (h(2)) for qualitatively assessed central lumbar spinal stenosis on MRI was 66.9% (95% confidence interval [95% CI] 56.8, 74.5). The broad-sense heritability estimate for dural sac cross-sectional area was 81.2% (95% CI 74.5, 86.1), with a similar magnitude of genetic influences across lumbar levels (h(2) = 72.4-75.6). The additive genetic correlation of quantitatively assessed stenosis and disc bulging was extremely high. There was no indication of shared genetic influences between stenosis and stature. ConclusionCentral lumbar spinal stenosis and associated dural sac dimensions are highly genetic, and disc degeneration (bulging) appears to be one pathway through which genes influence spinal stenosis.
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| 3. |
- Mayes, Maureen D, et al.
(författare)
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Immunochip analysis identifies multiple susceptibility Loci for systemic sclerosis.
- 2014
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Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297 .- 1537-6605. ; 94:1, s. 47-61
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Tidskriftsartikel (refereegranskat)abstract
- In this study, 1,833 systemic sclerosis (SSc) cases and 3,466 controls were genotyped with the Immunochip array. Classical alleles, amino acid residues, and SNPs across the human leukocyte antigen (HLA) region were imputed and tested. These analyses resulted in a model composed of six polymorphic amino acid positions and seven SNPs that explained the observed significant associations in the region. In addition, a replication step comprising 4,017 SSc cases and 5,935 controls was carried out for several selected non-HLA variants, reaching a total of 5,850 cases and 9,401 controls of European ancestry. Following this strategy, we identified and validated three SSc risk loci, including DNASE1L3 at 3p14, the SCHIP1-IL12A locus at 3q25, and ATG5 at 6q21, as well as a suggested association of the TREH-DDX6 locus at 11q23. The associations of several previously reported SSc risk loci were validated and further refined, and the observed peak of association in PXK was related to DNASE1L3. Our study has increased the number of known genetic associations with SSc, provided further insight into the pleiotropic effects of shared autoimmune risk factors, and highlighted the power of dense mapping for detecting previously overlooked susceptibility loci.
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