| 1. |
- Douglas, K. B., et al.
(författare)
-
Complement receptor 2 polymorphisms associated with systemic lupus erythematosus modulate alternative splicing
- 2009
-
Ingår i: Genes and Immunity. - : Springer Science and Business Media LLC. - 1466-4879 .- 1476-5470. ; 10:5, s. 457-469
-
Tidskriftsartikel (refereegranskat)abstract
- Genetic factors influence susceptibility to systemic lupus erythematosus (SLE). A recent family-based analysis in Caucasian and Chinese populations provided evidence for association of single-nucleotide polymorphisms (SNPs) in the complement receptor 2 (CR2/CD21) gene with SLE. Here we confirmed this result in a case-control analysis of an independent European-derived population including 2084 patients with SLE and 2853 healthy controls. A haplotype formed by the minor alleles of three CR2 SNPs (rs1048971, rs17615, rs4308977) showed significant association with decreased risk of SLE (30.4% in cases vs 32.6% in controls, P=0.016, OR=0.90 (0.82-0.98)). Two of these SNPs are in exon 10, directly 5' of an alternatively spliced exon preferentially expressed in follicular dendritic cells (FDC), and the third is in the alternatively spliced exon. Effects of these SNPs and a fourth SNP in exon 11 (rs17616) on alternative splicing were evaluated. We found that the minor alleles of these SNPs decreased splicing efficiency of exon 11 both in vitro and ex vivo. These findings further implicate CR2 in the pathogenesis of SLE and suggest that CR2 variants alter the maintenance of tolerance and autoantibody production in the secondary lymphoid tissues where B cells and FDCs interact.
|
|
| 2. |
- Kozyrev, Sergey V, et al.
(författare)
-
Functional variants in the B-cell gene BANK1 are associated with systemic lupus erythematosus
- 2008
-
Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 40:2, s. 211-216
-
Tidskriftsartikel (refereegranskat)abstract
- Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease characterized by production of autoantibodies and complex genetic inheritance(1-3). In a genome-wide scan using 85,042 SNPs, we identified an association between SLE and a nonsynonymous substitution (rs10516487, R61H) in the B-cell scaffold protein with ankyrin repeats gene, BANK1. We replicated the association in four independent case-control sets (combined P = 3.7 x 10(-10); OR = 1.38). We analyzed BANK1 cDNA and found two isoforms, one full-length and the other alternatively spliced and lacking exon 2 (Delta 2), encoding a protein without a putative IP3R-binding domain. The transcripts were differentially expressed depending on a branch point-site SNP, rs17266594, in strong linkage disequilibrium (LD) with rs10516487. A third associated variant was found in the ankyrin domain (rs3733197, A383T). Our findings implicate BANK1 as a susceptibility gene for SLE, with variants affecting regulatory sites and key functional domains. The disease-associated variants could contribute to sustained B cell-receptor signaling and B-cell hyperactivity characteristic of this disease.
|
|
| 3. |
- Abelson, Anna-Karin, et al.
(författare)
-
No evidence of association between genetic variants of the PDCD1 ligands and SLE
- 2007
-
Ingår i: Genes and Immunity. - : Springer Science and Business Media LLC. - 1466-4879 .- 1476-5470. ; 8:1, s. 69-74
-
Tidskriftsartikel (refereegranskat)abstract
- PDCD1, an immunoreceptor involved in peripheral tolerance has previously been shown to be genetically associated with systemic lupus erythematosus (SLE). PDCD1 has two ligands whose genes are located in close proximity on chromosome 9p24. Our attention was drawn to these ligands after finding suggestive linkage to a marker (gata62f03, Z=2.27) located close to their genes in a genome scan of Icelandic families multiplex for SLE. Here, we analyse Swedish trios (N=149) for 23 single nucleotide polymorphisms (SNPs) within the genes of the PDCD1 ligands. Initially, indication of association to eight SNPs was observed, and these SNPs were therefore also analysed in Mexican trios (N=90), as well as independent sets of patients and controls from Sweden (152 patients, 448 controls) and Argentina (288 patients, 288 controls). We do not find support for genetic association to SLE. This is the first genetic study of SLE and the PDCD1 ligands and the lack of association in several cohorts implies that these genes are not major risk factors for SLE.
|
|
| 4. |
- Abelson, Anna-Karin, et al.
(författare)
-
STAT4 Associates with SLE through two independent effects that correlate with gene expression and act additively with IRF5 to increase risk
- 2009
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967 .- 1468-2060. ; 68:11, s. 1746-1753
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To confirm and define the genetic association of STAT4 and systemic lupus erythematosus, investigate the possibility of correlations with differential splicing and/or expression levels, and genetic interaction with IRF5. METHODS: 30 tag SNPs were genotyped in an independent set of Spanish cases and controls. SNPs surviving correction for multiple tests were genotyped in 5 new sets of cases and controls for replication. STAT4 cDNA was analyzed by 5'-RACE PCR and sequencing. Expression levels were measured by quantitative PCR. RESULTS: In the fine-mapping, four SNPs were significant after correction for multiple testing, with rs3821236 and rs3024866 as the strongest signals, followed by the previously associated rs7574865, and by rs1467199. Association was replicated in all cohorts. After conditional regression analyses, two major independent signals represented by SNPs rs3821236 and rs7574865, remained significant across the sets. These SNPs belong to separate haplotype blocks. High levels of STAT4 expression correlated with SNPs rs3821236, rs3024866 (both in the same haplotype block) and rs7574865 but not with other SNPs. We also detected transcription of alternative tissue-specific exons 1, indicating presence of tissue-specific promoters of potential importance in the expression of STAT4. No interaction with associated SNPs of IRF5 was observed using regression analysis. CONCLUSIONS: These data confirm STAT4 as a susceptibility gene for SLE and suggest the presence of at least two functional variants affecting levels of STAT4. Our results also indicate that both genes STAT4 and IRF5 act additively to increase risk for SLE.
|
|
| 5. |
|
|
| 6. |
- Hanly, J G, et al.
(författare)
-
Autoantibodies and neuropsychiatric events at the time of systemic lupus erythematosus diagnosis
- 2008
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 58:3, s. 843-853
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. To examine, in an inception cohort of systemic lupus erythematosus (SLE) patients, the association between neuropsychiatric (NP) events and anti-ribosomal P (anti-P), antiphospholipid (lupus anticoagulant [LAC], anticardiolipin), anti-beta 2-glycoprotein I, and anti-NR2 glutamate receptor antibodies. Methods. NP events were identified using the American College of Rheumatology case definitions and clustered into central/peripheral and diffuse/focal events. Attribution of NP events to SLE was determined using decision rules of differing stringency. Autoantibodies were measured without knowledge of NP events or their attribution. Results. Four hundred twelve patients were studied (87.4% female; mean +/- SD age 34.9 +/- 13.5 years, mean +/- SD disease duration 5.0 +/- 4.2 months). There were 214 NP events in 133 patients (32.3%). The proportion of NP events attributed to SLE varied from 15% to 36%. There was no association between autoantibodies and NP events overall. However, the frequency of anti-P antibodies in patients with central NP events attributed to SLE was 4 of 20 (20%), versus 3 of 107 (2.8%) in patients with other NP events and 24 of 279 (8.6%) in those with no NP events (P = 0.04). Among patients with diffuse NP events, 3 of 11 had anti-P antibodies (27%), compared with 4 of 111 patients with other NP events (3.6%) and 24 of 279 of those with no NP events (8.6%) (P 0.02). Specific clinical-serologic associations were found between anti-P and psychosis attributed to SLE (P = 0.02) and between LAC and cerebrovascular disease attributed to SLE (P = 0.038). There was no significant association between other autoantibodies and NP events. Conclusion. Clinically distinct NP events attributed to SLE and occurring around the time of diagnosis were found to be associated with anti-P antibodies and LAC. This Suggests that there are different autoimmune pathogenetic mechanisms, although low sensitivity limits the clinical application of testing for these antibodies.
|
|
| 7. |
- Hanly, J. G., et al.
(författare)
-
Neuropsychiatric events at the time of diagnosis of systemic lupus erythematosus - An international inception cohort study
- 2007
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 56:1, s. 265-273
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. To describe the prevalence, characteristics, attribution, and clinical significance of neuropsychiatric (NP) events in an international inception cohort of systemic lupus erythematosus (SLE) patients. Methods. The study was conducted by the Systemic Lupus International Collaborating Clinics (SLICC). Patients were enrolled within 15 months of fulfilling the American College of Rheumatology (ACR) SLE classification criteria. All NP events within a predefined enrollment window were identified using the ACR case definitions of 19 NP syndromes. Decision rules were derived to determine the proportion of NP disease attributable to SLE. Clinical significance was determined using the Short Form 36 (SF-36) Health Survey and the SLICC/ACR Damage Index (SDI). Results. A total of 572 patients (88% female) were recruited, with a mean +/- SD age of 35 +/- 14 years. The mean +/- SD disease duration was 5.2 +/- 4.2 months. Within the enrollment window, 158 of 572 patients (28%) had at least 1 NP event. In total, there were 242 NP events that encompassed 15 of 19 NP syndromes. The proportion of NP events attributed to SLE varied from 19% to 38% using alternate attribution models and occurred in 6.1-11.7% of patients. Those with NP events, regardless of attribution, had lower scores on the SF-36 and higher SDI scores compared with patients with no NP events. Conclusion. Twenty-eight percent of SLE patients experienced at least 1 NP event around the time of diagnosis of SLE, of which only a minority were attributed to SLE. Regardless of attribution, the occurrence of NP events was associated with reduced quality of life and increased organ damage.
|
|
| 8. |
- Hanly, J. G., et al.
(författare)
-
Short-term outcome of neuropsychiatric events in systemic lupus erythematosus upon enrollment into an international inception cohort study
- 2008
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 1529-0131 .- 0004-3591. ; 59:5, s. 721-729
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. To determine the short-term outcome of neuropsychiatric (NP) events upon enrollment into an international inception cohort of patients with systemic lupus erythematosus (SLE). Methods. The study was performed by the Systemic Lupus International Collaborating Clinics. Patients were enrolled within 15 months of SLE diagnosis and NP events were characterized using the American College of Rheumatology case definitions. Decision rules were derived to identify NP events attributable to SLE. Physician outcome scores of NP events and patient-derived mental component summary (MCS) and physical component summary (PCS) scores of the Short Form 36 were recorded. Results. There were 890 patients (88.7% female) with a mean +/- SD age of 33.8 +/- 13.4 years and mean disease duration of 5.3 +/- 4.2 months. Within the enrollment window, 271 (33.5%) of 890 patients had at least 1 NP event encompassing 15 NP syndromes. NP events attributed to SLE varied from 16.5% to 33.9% using alternate attribution models and occurred in 6.0-11.5% of patients. Outcome scores for NP events attributed to SLE were significantly better than for NP events due to non-SLE causes. Higher global disease activity was associated with worse outcomes. MCS scores were lower in patients with NP events, regardless of attribution, and were also lower in patients with diffuse and central NP events. There was a significant association between physician outcome scores and patient MCS scores only for NP events attributed to SLE. Conclusion. In SLE patients, the short-term outcome of NP events is determined by both the characteristics and attribution of the events. Conclusion. In SLE patients, the short-term outcome of NP events is determined by both the characteristics and attribution of the events.
|
|
| 9. |
- Kozyrev, Sergey, et al.
(författare)
-
Structural insertion/deletion variation in IRF5 is associated with a risk haplotype and defines the precise IRF5 isoforms expressed in systemic lupus erythematosus
- 2007
-
Ingår i: Arthritis and Rheumatism. - : Wiley. - 0004-3591 .- 1529-0131. ; 56:4, s. 1234-1241
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. To determine whether specific isoforms of IRF5 are transcribed in patients with systemic lupus erythematosus (SLE) who have risk genotypes in the exon 1B donor splice site at single-nucleotide polymorphism (SNP) no. rs2004640. Methods. Peripheral blood mononuclear cells were obtained from SLE patients and healthy controls from Argentina, Spain, and Germany and from trio families from Spain and Denmark. A reporter assay was used to investigate the role of SNP no. rs2004640. IRF5 expression in relation to the genotypes of functional SNPs was analyzed using quantitative polymerase chain reaction. Sequencing and genotyping of the IRF5 gene was performed. Results. Sequencing of complementary DNA from individuals with different genotypes showed 4 basic isoforms transcribed from all 5′-untranslated regions (5′-UTRs), suggesting no preferential isoform transcription based on rs2004640 genotypes. Analysis of translation efficiency showed that exon 1A was the most efficient in initiating protein synthesis. We identified a novel polymorphic insertion/deletion that defines the pattern of expression of isoforms of IRF5. The insertion consists of 4 repeats in exon 6 affecting the protein interaction domain. The insertion segregates in the risk haplotype with the high expression allele of a poly(A) site SNP no. rs10954213 and the exon 1B donor splice allele of the 5′-UTR SNP no. rs2004640. The poly(A) polymorphism correlated with levels of IRF5 in cells stimulated with interferon-α. The SNP most strongly associated with SLE was SNP no. rs2070197 (P = 5.2 × 10 -11), which is a proxy of the risk haplotype, but does not appear to be functional. Conclusion. None of the functional variants investigated in this study is strongly associated with SLE, with the exception of the exon 1B donor splice site, and its functional importance appears to be small. Our results suggest that there may be other functional polymorphisms, yet to be identified, in IRF5. We did not observe evidence of epistatic interaction between the functional SNPs.
|
|
| 10. |
- Kozyrev, Sergey V., et al.
(författare)
-
The genetics and biology of Irf5-mediated signaling in lupus
- 2007
-
Ingår i: Autoimmunity. - : Informa UK Limited. - 0891-6934 .- 1607-842X. ; 40:8, s. 591-601
-
Tidskriftsartikel (refereegranskat)abstract
- Recently much attention was attracted to the importance of the type I interferon pathway in the initiation and development of the autoimmune disease systemic lupus erythematosus (SLE). Many SLE patients have increased serum levels of IFN-α and display an IFN gene expression "signature" characterized by strong overexpression of IFN-responsive genes in leukocytes and target tissues. Moreover, about 20% of cancer patients treated with IFN-α therapy manifest symptoms resembling SLE and some later develop the disease. One of the key genes of the IFN-α pathway, IRF5, was found to be strongly associated with SLE. Two functional SNPs lead to alternative splicing and altered steady-state level of IRF5 gene expression. Besides, the gene has a polymorphic inserion/deletion in exon 6, which contributes to the diversity in the isoform pattern of IRF5. Interestingly, recent studies have not found association of IRF5 with the other autoimmune diseases, such as rheumatoid arthritis or psoriasis, suggesting the unique role for IRF5 in the development of lupus. Here, we present the current knowledge on IRF5 genetics and its biological function and discuss the possible ways in which IRF5 contributes to susceptibility to SLE.
|
|
