Haplotype structure of TNFRSF5-TNFSF5 (CD40–CD40L) and association analysis in systemic lupus erythematosus

Epigenetics of Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease with non-suppurative destruction of the intrahepatic bile ducts. The interplay of genetics and environmental triggers contributes to the onset of the disease and subsequently results in cholestasis and progressive fibrosis. Recently, genome-wide association studies (GWAS) have identified multiple genes influencing the susceptibility to PBC in HLA and non-HLA loci. However, it is estimated that the known risk variants merely account for no more than 20% of the heritability of PBC and causes of the remaining heritability remain uncertain. Increasing evidence suggests that the presence of epigenetic abnormalities may explain the "missing heritability" that cannot be captured by GWAS. Among these epigenetic mechanisms, DNA methylation, histone modification, and noncoding RNAs (i.e. miRNA and lncRNA) are involved in the pathogenesis of PBC. Additionally, telomere dysregulation in biliary epithelial cells (BECs) may play a role in disease onset, whereas a deficiency in sex chromosome and skewed gene expression in the X chromosome may to some extent explain the female dominance in PBC.

Association of soluble CD40 levels with -1 C > T CD40 polymorphism and chronic kidney disease in systemic lupus erythematosus

Background

CD40 is a transmembrane protein mainly expressed on the antigen‐presenting cells surface. CD40 plays a crucial role in immunoglobulin class switching and antibodies production. Genetic polymorphisms in the CD40 gene have been associated with increased risk of systemic lupus erythematosus (SLE) in several populations. This study aimed to evaluate the association of CD40 polymorphisms (−1 C > T, rs1883832 and 6,048 G > T, rs4810485) with SLE susceptibility, as well as with mRNA expression and soluble CD40 (sCD40) levels.

Methods

The study included 293 patients with SLE and 294 control subjects (CS). Genotyping was performed by PCR‐RFLP method. CD40 mRNA expression was determined by quantitative real‐time PCR, and ELISA quantified sCD40 levels.

Results

The CD40 polymorphisms −1 C > T and 6,048 G > T were associated with SLE susceptibility. There was no difference between CD40 mRNA expression and CD40 polymorphisms. The sCD40 levels were lower in SLE patients with TT haplotype, whereas higher sCD40 levels were associated with damage and impaired renal function according to SLICC and KDIGO. The sCD40 levels were negatively correlated with eGFR.

Conclusion

The CD40 gene polymorphisms increase the risk of SLE in the western Mexican population. The sCD40 levels are associated with −1 C > T polymorphism and chronic kidney disease.

Association between CD40 polymorphisms and systemic lupus erythematosus and correlation between soluble CD40 and CD40 ligand levels in the disease: a meta-analysis

Objective

The aim of this study was to systematically review evidence regarding the association between CD40 polymorphisms and systemic lupus erythematosus and between soluble CD40 (sCD40) and CD40 ligand (sCD40L) levels and systemic lupus erythematosus.

Methods

We performed a meta-analysis on the association between CD40 rs4810495, rs1883832, and rs376545 polymorphisms and systemic lupus erythematosus risk and sCD40/sCD40L levels in patients with systemic lupus erythematosus and controls.

Results

Fourteen studies were included. Ethnicity-specific meta-analysis indicated a significant association between the T allele of CD40 rs4810485 polymorphism and systemic lupus erythematosus in Europeans (odds ratio = 0.715, 95% confidence interval = 0.641–0.832, p < 0.001) and a trend toward an association between the T allele and systemic lupus erythematosus in Asians (odds ratio = 1.255, 95% confidence interval = 0.978–1.810, p = 0.074). Furthermore, a significant association was reported between systemic lupus erythematosus and the C allele of CD40 rs1883832 polymorphism (odds ratio = 1.235, 95% confidence interval = 1.087–1.405, p = 0.001) and A allele of CD40 rs3765456 polymorphism and systemic lupus erythematosus in Asians (odds ratio = 1.184, 95% confidence interval = 1.040–1.348, p = 0.011). sCD40 and sCD40L levels were significantly higher in SLE than in controls (standardized mean difference = 1.564, 95% confidence interval = 0.256–2.872, p = 0.019 and standardized mean difference = 1.499, 95% confidence interval = 1.031–1.967, p < 0.001, respectively). Stratification based on ethnicity revealed higher sCD40L levels in the systemic lupus erythematosus group among European, Asian, North American, and Arab populations.

Conclusions

Our meta-analyses found associations between CD40 rs4810495, rs1883832, and rs376545 polymorphisms and systemic lupus erythematosus susceptibility and significantly higher sCD40 and sCD40L levels in patients with systemic lupus erythematosus than in controls.

Analysis of Genetic Variation in CD40 and CD40L: Relationship with mRNA Relative Expression and Soluble Proteins in Acute Coronary Syndrome

Acute coronary syndrome (ACS) can be triggered by the presence of inflammatory factors which promote the activation of immune cells by costimulatory molecules such as CD40 and its ligand CD40L. Environmental and genetic factors are involved in the etiology of the ACS. The aim of this study was to explore the gene and protein expression associated with CD40 and CD40L genetic variants in ACS patients from the western Mexican population. A total of 620 individuals from western Mexico were recruited: 320 ACS patients and 300 individuals without a history of ischemic cardiopathy were evaluated. The genotype was determined using TaqMan SNP genotyping assays. CD40 and CD40L expressions at the mRNA level were quantified using TaqMan Gene Expression Assays. Soluble protein isoforms were measured by enzyme-linked immunosorbent assay. We did not find evidence of association between CD40 (rs1883832, rs4810485, and rs11086998) and CD40L (rs3092952 and rs3092920) genetic variants and susceptibility to ACS, although rs1883832 and rs4810485 were significantly associated with high sCD40 plasma levels. Plasma levels of sCD40L can be affected by gender and the clinical spectrum of acute coronary syndrome. Our results do not suggest a functional role of CD40 and CD40L genetic variants in ACS. However, they could reflect the inflammatory process and platelet activation in ACS patients, even when they are under pharmacological therapy. Due to the important roles of the CD40-CD40L system in the pathogenesis of ACS, longitudinal studies are required to determine if soluble levels of CD40 and CD40L could be clinically useful markers of a recurrent cardiovascular event after an ACS.

Levels of human platelet-derived soluble CD40 ligand depend on haplotypes of CD40LG-CD40-ITGA2

Increased circulating soluble CD40 ligand (sCD40L) is commonly associated with inflammatory disorders. We aimed to investigate whether gene polymorphisms in CD40LG, CD40 and ITGA2 are associated with a propensity to secrete sCD40L; thus, we examined this issue at the level of human platelets, the principal source of sCD40L. We performed single polymorphism and haplotype analyses to test for the effect of twelve polymorphisms across the CD40LG, CD40 and ITGA2 genes in blood donors. ITGA2 presented a positive association with rs1126643, with a significant modification in sCD40L secretion (carriers of C allele, P = 0.02), unlike the investigated CD40LG and CD40 polymorphisms. One CD40LG haplotype (TGGC) showing rs975379 (C/T), rs3092952 (A/G), rs3092933 (A/G) and rs3092929 (A/C) was associated with increased sCD40L levels (1.906 μg/L (95% CI: 1.060 to 2.751); P = 0.000009). The sCD40L level was associated with the inter-chromosomal CD40LG/CD40/ITGA2 haplotype (ATC), displaying rs3092952 (A/G), rs1883832 (C/T) and rs1126643 (C/T), with increased sCD40L levels (P = 0.0135). Our results help to decipher the genetic role of CD40LG, CD40 and ITGA2 with regard to sCD40L levels found in platelet components. Given the crucial role of sCD40L, this haplotype study in a transfusion model may be helpful to further determine the role of haplotypes in inflammatory clinical settings.

Development of a highly resolutive method, using a double quadruplex tetra-primer-ARMS-PCR coupled with capillary electrophoresis to study CD40LG polymorphisms

Polymorphisms in the CD40 ligand gene (CD40LG) are associated with various immunological disorders such as tumors, autoimmune and infectious diseases. The aim of this study was to develop a highly optimized double quadruplex tetra-primer amplification refractory mutation system PCR (double quadruplex T-ARMS-PCR) coupled with capillary electrophoresis to allow genotyping of eight relevant candidate CD40LG SNPs and to establish haplotypes. After conducting the double quadruplex T-ARMS-PCR, the genotypes obtained through agarose electrophoresis were compared with those obtained through capillary electrophoresis. This strategy was applied to analyze the genetic patterns of CD40LG in two distinct cohorts of blood donors (211 French and 274 Tunisian). The T-ARMS-PCR method was rapid, inexpensive, reproducible and reliable for SNP determination. Regarding the separation technique, capillary electrophoresis allows traceable and semi-automated analysis while agarose electrophoresis remains a cost-effective technique that does not require specialized or costly equipment. Using these methods, we identified significantly different genetic heterogeneity between the two investigated populations (p ≤ 0.0001) and we also extensively characterized their haplotypes. The obtained genotype distribution and the optimized quadruplex T-ARMS-PCR technique coupled with capillary electrophoresis provides valuable information for studying pathologic inflammation leading to various diseases in which CD40LG might be a candidate gene.

Are polymorphisms of the immunoregulatory factor CD40LG implicated in acute transfusion reactions?

The CD40 ligand (CD40L/CD154), a member of TNF superfamily, is notably expressed on activated CD4+ T-cells and stimulated platelets. CD40L is linked to a variety of pathologies and to acute transfusion reactions (ATR). Mutations in this gene (CD40LG) lead to X-linked hyper-IgM syndrome. Some CD40LG polymorphisms are associated with variable protein expression. The rationale behind this study is that CD40L protein has been observed to be involved in ATR. We wondered whether genetic polymorphisms are implicated. We investigated genetic diversity in the CD40LG using DHPLC and capillary electrophoresis for screening and genotyping (n = 485 French and Tunisian blood donors). We identified significant difference in the CD40LG linkage pattern between the two populations. Variant minor alleles were significantly over-represented in Tunisian donors (P<0.0001 to 0.0270). We found higher heterogeneity in the Tunisian, including three novel low frequency variants. As there was not a particular pattern of CD40LG in single apheresis donors whose platelet components induced an ATR, we discuss how this information may be useful for future disease association studies on CD40LG.

Association of genetic polymorphisms in CD40 with susceptibility to SLE in the Korean population

OBJECTIVE

The aim of this study was to examine the association of CD40 polymorphisms with the risk of SLE in the Korean population.

METHODS

A total of 601 Korean SLE patients and 984 healthy controls were enrolled. We selected seven CD40 gene SNPs based on previous results of CD40 gene sequencing in the Korean population. Statistical analysis was carried out by logistic regression, controlling for age and sex as covariates. Odds ratios (ORs) and P-values in co-dominant, dominant and recessive models were also calculated.

RESULTS

SNP rs3765456 showed significant association with risk of SLE (OR = 1.34, P = 0.007, Pcorr = 0.03) in the dominant model. SNPs rs1883832 and rs4810485, and haplotype 2 (GTTCTAA) were also associated with the risk of SLE in the dominant model, but statistical significance disappeared after correction for multiple testing. Haplotype 2 had a protective effect on LN (OR = 0.47, P = 0.01, Pcorr = 0.05) in the recessive model while rs73115010, rs6074028 and haplotype 3 (ACGTCGG) resulted in increased risk of arthritis in the recessive model (OR = 2.87, 2.76 and 2.46, P = 0.002, 0.004 and 0.01, Pcorr = 0.009, 0.02 and 0.05, respectively).

CONCLUSION

CD40 gene polymorphisms are possible risk factors for SLE development, especially rs3765456 in the dominant model. CD40 polymorphisms are also associated with SLE clinical manifestation, mainly nephritis and arthritis. Further replication with larger numbers, and populations of different ethnicities, are needed to confirm our findings.

Study of association of CD40-CD154 gene polymorphisms with disease susceptibility and cardiovascular risk in Spanish rheumatoid arthritis patients

Objective

Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with increased cardiovascular (CV) mortality. Since CD40-CD154 binding has direct consequences on inflammation process initiation, we aimed to replicate previous findings related to disease susceptibility in Spanish RA population. Furthermore, as the major complication in RA disease patients is the development of CV events due to accelerated atherosclerosis, and elevated levels of CD40L/CD154 are present in patients with acute myocardial infarction, we assessed the potential association of CD40 and CD154/CD40L gene variants with CV risk in Spanish RA patients.

Methods

One thousand five hundred and seventy-five patients fulfilling the 1987 ACR classification criteria for RA and 1600 matched controls were genotyped for the CD40 rs1883832, rs4810485 and rs1535045 and CD154 rs3092952 and rs3092920 gene polymorphisms, using predesigned TaqMan single nucleotide polymorphism genotyping assays. Afterwards, we investigated the influence of CD40-CD154 gene variants in the development of CV events. Also, in a subgroup of 273 patients without history of CV events, we assessed the influence of these polymorphisms in the risk of subclinical atherosclerosis determined by carotid ultrasonography.

Results

Nominally significant differences in the allele frequencies for the rs1883832 CD40 gene polymorphism between RA patients and controls were found (p = 0.038). Although we did not observe a significant association of CD40-CD154 gene variants with the development of CV events, an ANCOVA model adjusted for sex, age at the time of the ultrasonography assessment, follow-up time, traditional CV risk factors and anti-cyclic citrullinated peptide antibodies disclosed a significant association (p = 0.0047) between CD40 rs1535045 polymorphism and carotid intima media thickness, a surrogate marker of atherosclerosis.

Conclusion

Data from our pilot study indicate a potential association of rs1883832 CD40 gene polymorphism with susceptibility to RA. Also, the CD40 rs1535045 gene variant may influence development of subclinical atherosclerosis in RA patients.

Analysis of the association between CD40 and CD40 ligand polymorphisms and systemic sclerosis

Introduction

The aim of the present study was to investigate the possible role of CD40 and CD40 ligand (CD40LG) genes in the susceptibility and phenotype expression of systemic sclerosis (SSc).

Methods

In total, 2,670 SSc patients and 3,245 healthy individuals from four European populations (Spain, Germany, The Netherlands, and Italy) were included in the study. Five single-nucleotide polymorphisms (SNPs) of CD40 (rs1883832, rs4810485, rs1535045) and CD40LG (rs3092952, rs3092920) were genotyped by using a predesigned TaqMan allele-discrimination assay technology. Meta-analysis was assessed to determine whether an association exists between the genetic variants and SSc or its main clinical subtypes.

Results

No evidence of association between CD40 and CD40LG genes variants and susceptibility to SSc was observed. Similarly, no significant statistical differences were observed when SSc patients were stratified by the clinical subtypes, the serologic features, and pulmonary fibrosis.

Conclusions

Our results do not suggest an important role of CD40 and CD40LG gene polymorphisms in the susceptibility to or clinical expression of SSc.

A common SNP in the CD40 region is associated with systemic lupus erythematosus and correlates with altered CD40 expression: implications for the pathogenesis

BACKGROUND

In systemic lupus erythematosus (SLE) sustained CD40L expression by T cells and platelets activates a variety of cells via its receptor CD40 contributing to disease pathogenesis. Although CD40 has recently been identified in genome-wide association study as a novel rheumatoid arthritis susceptibility gene such an association has not been documented for SLE.

OBJECTIVE

To investigate whether the rs4810485 CD40 single nucleotide polymorphism (SNP) is associated with increased risk for SLE and its impact on CD40 expression.

MATERIALS AND METHODS

The primary sample set consisted of 351 patients with SLE and 670 matched healthy controls of Greek origin. 158 patients with SLE and 155 controls from Turkey were used as a replication sample. Genotyping of rs4810485 was performed by restriction fragment length polymorphism and the Sequenom MassArray technology. The expression of CD40 mRNA and protein was assessed in unstimulated and lipopolysaccharide-stimulated peripheral blood mononuclear cells by quantitative real time PCR and flow cytometry, respectively.

RESULTS

The minor allele T of CD40 rs4810485 SNP was significantly under-represented in Greek patients with SLE compared with healthy controls (OR=0.65, 95% CI 0.54 to 0.79). The association was replicated in the Turkish cohort (OR=0.57, 95% CI 0.41 to 0.80; meta-analysis of 509 patients with SLE and 825 healthy controls: OR=0.63, 95% CI 0.53 to 0.74, p = 2×10(-8)). In both cases and controls, the rs4810485 G/T and T/T genotypes were associated with significantly reduced CD40 mRNA and protein expression in peripheral blood CD14+ monocytes and CD19+ B cells compared with G/G genotype, both under basal conditions and following stimulation.

CONCLUSIONS

CD40 has been identified as a new susceptibility locus in Greek and Turkish patients with SLE. The rs4810485 minor allele T is under-represented in SLE and correlates with reduced CD40 expression in peripheral blood monocytes and B cells, with potential implications for the regulation of aberrant immune responses in the disease.

Association of EBF1, FAM167A(C8orf13)-BLK and TNFSF4 gene variants with primary Sjögren's syndrome

We performed a candidate gene association study in 540 patients with primary Sjögren's Syndrome (SS) from Sweden (n=344) and Norway (n=196) and 532 controls (n=319 Swedish, n=213 Norwegian). A total of 1139 single-nucleotide polymorphisms (SNPs) in 84 genes were analyzed. In the meta-analysis of the Swedish and Norwegian cohorts, we found high signals for association between primary SS and SNPs in three gene loci, not previously associated with primary SS. These are the early B-cell factor 1 (EBF1) gene, P=9.9 × 10(-5), OR 1.68, the family with sequence similarity 167 member A-B-lymphoid tyrosine kinase (FAM167A-BLK) locus, P=4.7 × 10(-4), OR 1.37 and the tumor necrosis factor superfamily (TNFSF4=Ox40L) gene, P=7.4 × 10(-4), OR 1.34. We also confirmed the association between primary SS and the IRF5/TNPO3 locus and the STAT4 gene. We found no association between the SNPs in these five genes and the presence of anti-SSA/anti-SSB antibodies. EBF1, BLK and TNFSF4 are all involved in B-cell differentiation and activation, and we conclude that polymorphisms in several susceptibility genes in the immune system contribute to the pathogenesis of primary SS.

Autoantibody-dependent and autoantibody-independent roles for B cells in systemic lupus erythematosus: past, present, and future

It has long been known that B cells produce autoantibodies and, thereby, contribute to the pathogenesis of many autoimmune diseases. Systemic lupus erythematosus (SLE), a prototypic systemic autoimmune disorder, is characterized by high-circulating autoantibody titers and immune-complex deposition that can trigger inflammatory damage in multiple organs/organ systems. Although the interest in B cells in SLE has historically focused on their autoantibody production, we now appreciate that B cells have multiple autoantibody-independent roles in SLE as well. B cells can efficiently present antigen and activate T cells, they can augment T cell activation through co-stimulatory interactions, and they can produce numerous cytokines which affect inflammation, lymphogenesis, and immune regulation. Not surprisingly, B cells have become attractive therapeutic targets in SLE. With these points in mind, this review will focus on the autoantibody-dependent and autoantibody-independent roles for B cells in SLE and on therapeutic approaches that target B cells.

A novel polymorphism of the human CD40 receptor with enhanced function

CD40 signaling is critical for innate and adaptive immunity against pathogens, and the cytoplasmic domain of CD40 is highly conserved both within and between species. A novel missense single nucleotide polymorphism (SNP) in the cytoplasmic domain of CD40 at position 227 (P227A) was identified, which resides on a conserved ancestral haplotype highly enriched in persons of Mexican and South American descent. Functional studies indicated that signaling via human (h) CD40-P227A stably expressed in several B-cell lines led to increased phosphorylation of c-Jun, increased secretion of the pro-inflammatory cytokines interleukin (IL)-6 and TNF-alpha, and increased Ig production, compared with wild-type hCD40. Cooperation between hCD40-P227A signaling and B-cell receptor (BCR)- or Toll-like receptor 9 (TLR9)-mediated signaling was also enhanced, resulting in elevated and synergistic production of IL-6 and Ig. We have thus identified a novel genetic variant of hCD40 with a gain-of-function immune phenotype.

Linkage disequilibrium patterns and functional analysis of RGS4 polymorphisms in relation to schizophrenia

The regulator of G-protein signaling 4 (RGS4, chromosome 1q23.3) plays a critical role in G-protein function. Four common single-nucleotide polymorphisms (SNPs) localized between the 5' upstream sequence and the first intron, as well as 2 haplotypes derived from these SNPs may confer liability to schizophrenia (SZ). However, the pattern of associations varies among samples. To help clarify the putative associations, we report the following analyses: (1) a comprehensive catalog of common polymorphisms, (2) linkage disequilibrium (LD) and association analyses using these SNPs, and (3) functional analysis based on dual-luciferase promoter assays. We identified 62 SNPs from a 20-kb genomic region spanning RGS4, of which 26 are common polymorphisms with a minor allele frequency (MAF) of >5%. LD analysis suggested 5 clusters of SNPs (r(2) > .8). Association analyses using the novel SNPs were consistent with the prior reports, but further localization was constrained by significant LD across the region. The 2 haplotypes reported to confer liability to SZ had significant promoter activity compared with promoterless constructs, suggesting a functional role for both haplotypes. Further analyses of promoter sequences are warranted to understand transcriptional regulation at RGS4. This information will be useful for further analysis of samples in which genetic association of RGS4 polymorphisms with SZ has been reported.

Molecular and functional analysis of a novel recombinant clone of rat (Rattus norvegicus) CD40 ligand (CD40L) gene

Genetic material obtained from various individuals may contain certain polymorphisms which may conflict with the predetermined DNA sequence and consequently, may modulate the function of gene products. In this study, coding sequence of rat CD40 ligand (CD40L, CD154) was obtained from activated splenocytes, amplified, and cloned into a eukaryotic expression vector by using directional cloning method. Sequence of the recombinant rat CD40L DNA, pCD40L-IRES2-EGFP (pCD40L), was compared with the previously reported rat CD40L cDNA sequences and a 99% identity was found. Differing nucleotides were on the positions; 122-T/C, 341-G/A, 476-G/A, 762-T/A. Further alignment analysis showed that pCD40L was collectively carrying the nucleotides each previously reported by different groups. The sequence was submitted to NCBI GenBank and nucleotide database accession number EF066490 was obtained. Following transfection of the construct into NIH/3T3 cell line, novel CD40L clone was functionally expressed de novo, increasing the expression of CD80 and CD86 costimulatory molecules and augmenting the proliferation rate of effector splenocytes in immune reactions ex vivo. Based on these data, here we report a novel recombinant clone of the rat CD40L gene which may represent a potential polymorphic variant.

Genetics of autoimmune diseases--disorders of immune homeostasis

In the past few years, our extensive knowledge of the mammalian immune system and our increasing ability to understand the genetic causes of complex human disease have opened a window onto the pathways that lead to autoimmune disorders. In addition to the well-established role of genetic variation that affects the major histocompatibility complex, a number of rare and common variants that affect a range of immunological pathways are now known to have important influences on the phenotypic diversity that is seen among autoimmune diseases. Recent studies have also highlighted a previously unanticipated interplay between the innate and adaptive immune system, providing a new direction for research in this field.

Dysregulation of TNF/TNFR superfamily members: a systemic link between intra- and extrathyroidal manifestations in Graves' disease

Graves' disease (GD) coincides with the occurrence of disease-associated intrathyroidal dendritic cells (DC) and intraorbital inflammatory macrophages (Mphi). Physiologically, tumour necrosis factor-alpha (TNF-alpha) strongly affects the differentiation of DC and Mphi from monocytic precursors; we thus hypothesized that dysregulation of the TNF/TNFR superfamilies may provide a systemic pathogenic link in GD. In patients without eye symptoms, percentages of TNF-alpha-stimulated blood monocytes were highly significantly (P < 0.001) elevated, corresponding to both intrathyroidal DC maturation as well as increases in mature blood DC (MHC-II(hi)/CD40+/RFD1(hi)) and B cells (CD20(hi)/CD40+). GD patients also displaying eye symptoms revealed a striking reduction in blood monocytes, yet significantly (P < 0.05) increased CD40(hi) and TNF-alpha(hi) leucocytes. These findings suggest for GD that excess TNF-alpha induces monocytes to differentiate into hyperactivated thyroidal DC that, once emigrated, initiate systemic humoral autoimmunity associated with CD40/TNF-alpha upregulation. Such overexpression may instigate differentiation of periorbital inflammatory Mphi from CD14(hi)/CD16+ monocytes as a likely precursor subset. These results indicate that dysregulation of TNF/TNFR superfamily members provides a systemic pathogenic link in GD in that hyperactivated circulating monocytic precursors give rise to locally restricted, disease-associated DC and Mphi. Monocytes, therefore, may serve as a suitable target to therapeutically address the common precursor of key promoters of GD.

Haplotype analysis of tumour necrosis factor receptor genes in 1p36: no evidence for association with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with partially understood aetiology. The 1p36 region has been previously linked with SLE and harbours tumour necrosis factor receptor (TNFR) genes. Functional and genetic data implicate their gene products in SLE and other autoimmune diseases. In all, single-nucleotide polymorphisms (SNPs) across TNFRSF14 (HVEM), and 43 SNPs across the TNFRSF8 (CD30) and TNFRSF1B (CD120B) locus were investigated for linkage disequilibrium (LD) and haplotype analysis in European-Caucasians. Strong LD was observed across HVEM and CD120B, and little LD and recombination across CD30. We also examined the association of SNPs and haplotypes in HVEM, CD30 and CD120B with SLE in European-Caucasians. There was no evidence of association for these genes in 456 European-Caucasian families with SLE from UK. Haplotype tagging SNPs are made known across areas of strong LD, which will facilitate analysis for susceptibility in other diseases.