Genetic variants within the TNFRSF1B gene and susceptibility to rheumatoid arthritis and response to anti-TNF drugs: a multicenter study.

BACKGROUND: Recent research suggests that genetic variants in the tumor necrosis factor receptor 2 (TNFRSF1B) gene may have an impact on susceptibility to rheumatoid arthritis (RA) and drug response. The present population-based case-control study was carried out to evaluate whether 5 tagging single-nucleotide polymorphisms (SNPs) within the TNFRSF1B gene are associated with the risk of RA and response to antitumor necrosis factor (TNF) drugs. METHODS: The study population included 1412 RA patients and 1225 healthy controls. A subset of 596 anti-TNF-naive RA patients was selected to assess the association of TNFRSF1B SNPs and drug response according to the EULAR response criteria. RESULTS: We found that carriers of the TNFRSF1Brs3397C allele had a significantly increased risk of developing RA (P=0.0006). Importantly, this association remained significant after correction for multiple testing. We also confirmed the lack of association of the TNFRSF1Brs1061622 SNP with the risk of RA in the single-SNP analysis (P=0.89), but also through well-powered meta-analyses (PDOM=0.67 and PREC=0.37, respectively). In addition, our study showed that carriers of the TNFRSF1Brs3397C/C, TNFRSF1Brs1061622G/G, and TNFRSF1Brs1061631A/A genotypes had an increased risk of having a worse response to anti-TNF drugs at the level of P less than 0.05 (P=0.014, 0.0085 and 0.028, respectively). We also observed that, according to a log-additive model, carriers of the TNFRSF1Brs3397C or TNFRSF1Brs1061622G alleles showed an increased risk of having worse response to anti-TNF medications (P=0.018 and 0.0059). However, the association of the TNFRSF1Brs1061622 SNP only reached marginal significance after correction for multiple testing according to a log-additive model (P=0.0059) and it was not confirmed through a meta-analysis (PDOM=0.12). CONCLUSION: Our results suggest that the TNFRSF1Brs3397 variant may play a role in modulating the risk of RA, but does not provide strong evidence of an impact of TNFRSF1B variants in determining response to anti-TNF drugs.

Allelic variants in TLR10 gene may influence bilateral affectation and clinical course of Meniere's disease.

Toll-like receptors trigger the innate immune response by activating various cell types such us macrophages and lymphocytes. We genotyped SNV of TLR3, TRL7, TLR8 and TLR10 in 863 Spanish and 150 Italian patients with Meniere's disease (MD) and 1,013 controls by using Taqman assays. Real-Time qPCR was used to measure the expression level of TLR10 in peripheral blood leukocytes. The overall dataset showed that the C allele and the CC genotype of rs11096955 in TLR10 gene were more commonly observed in controls than patients (corrected p = 1 × 10(-3), OR = 0.68 [95 % confidence interval, 0.54-0.84] for CC genotype; corrected p = 1.5 × 10(-5), OR = 0.75 [0.66-0.85] for allele C). Moreover, the CC genotype was more frequent in patients with uni- (19 %) than bilateral sensorineural hearing loss (SNHL) (13 %). Logistic regression demonstrated that the time since the onset of MD, Tumarkin crises, hearing stage and rs11096955 were independent factors influencing the risk of bilateral SNHL. In addition, rs11096955 influenced hearing loss progression in patients with bilateral MD. No change in expression of TLR10 was observed according to CC, CA or AA genotypes. Our data suggest that allelic variants of TLR10 gene may influence the susceptibility and time-course of hearing loss of MD in the European population.

Functional variants of MIF, INFG and TFNA genes are not associated with disease susceptibility or hearing loss progression in patients with Ménière's disease.

Variability in acute immune response genes could determine susceptibility or prognosis for Ménière's disease (MD). The cytokines tumor necrosis factor α (TNFα), macrophage migration inhibitory factor (MIF) and interferon γ (INFγ) are proinflammatory cytokines of the innate immune response. These cytokines mediate inflammation and have been previously associated with the inflammatory process in several autoimmune diseases. We investigated the association between functional allelic variants of MIF (rs35688089), IFNG (rs2234688) and TNFA (rs1800629) in patients with MD. In addition to testing these variants for an association with disease, we also tested for an association with clinical aspects of disease progression, such as persistence of vertigo and the sensorineural hearing loss. A total of 580 patients with diagnosis of definite MD, according to the diagnostic scale of the American Academy of Otolaryngology-Head and Neck Surgery, and 552 healthy controls were included. DNA samples from a set of 291 American patients were used to confirm the results obtained in the MIF gene in our Spanish cohort. Although we found a significant association with the allele containing five repeats of CATT within the MIF gene in patients with MD in the Spanish cohort [corrected p = 0.008, OR = 0.69 (95 % CI, 0.54-0.88)], this finding could not be replicated in the American set. Moreover, no genetic associations for variants in either the TNFA or IFNG genes and MD were found. These results support the conclusion that functional variants of MIF, INFG, and TFNA genes are not associated with disease susceptibility or hearing loss progression in patients with MD.

Human adipose tissue as a major reservoir of cytomegalovirus-reactive T cells.

Introduction: Cytomegalovirus (CMV) is a common herpesvirus with a high prevalence worldwide. After the acute infection phase, CMV can remain latent in several tissues. CD8 T cells in the lungs and salivary glands mainly control its reactivation control. White adipose tissue (WAT) contains a significant population of memory T cells reactive to viral antigens, but CMV specificity has mainly been studied in mouse WAT. Therefore, we obtained blood, omental WAT (oWAT), subcutaneous WAT (sWAT), and liver samples from 11 obese donors to characterize the human WAT adaptive immune landscape from a phenotypic and immune receptor specificity perspective. Methods: We performed high-throughput sequencing of the T cell receptor (TCR) locus to analyze tissue and blood TCR repertoires of the 11 donors. The presence of TCRs specific to CMV epitopes was tested through ELISpot assays. Moreover, phenotypic characterization of T cells was carried out through flow cytometry. Results: High-throughput sequencing analyses revealed that tissue TCR repertoires in oWAT, sWAT, and liver samples were less diverse and dominated by hyperexpanded clones when compared to blood samples. Additionally, we predicted the presence of TCRs specific to viral epitopes, particularly from CMV, which was confirmed by ELISpot assays. Remarkably, we found that oWAT has a higher proportion of CMV-reactive T cells than blood or sWAT. Finally, flow cytometry analyses indicated that most WAT-infiltrated lymphocytes were tissue-resident effector memory CD8 T cells. Discussion: Overall, these findings postulate human oWAT as a major reservoir of CMV-specific T cells, presumably for latent viral reactivation control. This study enhances our understanding of the adaptive immune response in human WAT and highlights its potential role in antiviral defense.

Reduction of false-negative papillary thyroid carcinomas by the routine analysis of BRAF(T1799A) mutation on fine-needle aspiration biopsy specimens: a prospective study of 814 thyroid FNAB patients.

OBJECTIVES: To evaluate prospectively the usefulness of the routine determination of BRAF(T1799A) mutation on thyroid fine-needle aspiration biopsy (FNAB) to detect cytopathology false negative papillary thyroid carcinomas (PTC) and, therefore, as a tool to improve the sensitivity of the preoperative cytopathological diagnosis of PTC in thyroid nodules. BACKGROUND: FNAB is the most reliable diagnostic test to discriminate between malignant and benign thyroid nodules, but nondiagnostic results remain a clinical management dilemma. BRAF(T1799A) mutation is the most prevalent genetic alteration in thyroid cancers and is specific for PTC, characteristics that make it the most potentially helpful genetic tool to improve the diagnostic accuracy of FNAB. METHODS: An exhaustive recruitment of all patients subjected to thyroid FNAB in our institution during 4 years was performed. BRAF(T1799A) mutation was determined on thyroid FNAB specimens by PCR and restriction fragment length polymorphism, plus direct sequencing in positive samples. RESULTS: BRAF(T1799A) mutation on FNAB detected 47.2% (17/36) of PTC cases. It confirmed preoperatively 45.5% (5/11) of the PTC cases in the indeterminate category and decreased the rate of cytopathology false-negatives in 33.3% (6/18), improving the combined (BRAF(T1799A) mutation + cytopathological analysis) sensitivity of the detection of PTC on FNAB in 16.7%. CONCLUSIONS: BRAF(T1799A) mutation improves the diagnosis of PTC on FNAB, mainly because of the detection of cytopathology false-negatives, and it can be helpful in the routine analysis of thyroid nodules, especially in clinical settings with moderate sensitivity to detect PTC on FNAB.

Analysis of Class II human leucocyte antigens in Italian and Spanish systemic sclerosis.

OBJECTIVE: To determine the role of Class II HLAs in SSc patients from Italy and Spain and in SSc patients of Caucasian ancestry. METHODS: Nine hundred and forty-four SSc patients (Italy 392 patients; Spain 452 patients) and 1320 ethnically matched healthy controls (Italy 398 patients; Spain 922 patients) were genotyped up to the fourth digit by PCR with sequence-specific oligonucleotides for HLA-DRB1, DQA1 and DQB1 loci. Patients included 390 ACA-positive and 254 anti-topo I-positive subjects. Associations between SSc or SSc-specific antibodies and HLA alleles or HLA haplotypes were sought via the chi-square test after 10 000-fold permutation testing. A meta-analysis including this study cohort and other Caucasoids samples was also conducted. RESULTS: In both the cohorts, the strongest association was observed between the HLA-DRB1*1104 allele and SSc or anti-topo I antibodies. The HLA-DRB1*1104 -DQA1*0501 -DQB1*0301 haplotype was overrepresented in Italian [odds ratio (OR) = 2.069, 95% asymptotic CIs (CI(95)) 1.486, 2.881; P < 0.001] and in Spanish patients (OR = 6.707, CI(95) 3.974, 11.319; P < 0.001) as well as in anti-topo-positive patients: Italy (OR = 2.642, CI(95) 1.78, 3.924; P < 0.001) and Spain (OR = 20.625, CI(95) 11.536, 36.876; P < 0.001). In both the populations we also identified an additional risk allele (HLA-DQB1*03) and a protective allele (HLA-DQB1*0501) in anti-topo-positive patients. The meta-analysis showed different statistically significant associations, the most interesting being the differential association between HLA-DRB1*01 alleles and ACAs (OR = 1.724, CI(95) 1.482, 2.005; P < 0.001) or topo I antibodies (OR = 0.5, CI(95) 0.384, 0.651; P < 0.001). CONCLUSIONS: We describe multiple robust associations between SSc and HLA Class II antigens in Caucasoids that may help to understand the genetic architecture of SSc.

Identification of a new putative functional IL18 gene variant through an association study in systemic lupus erythematosus.

Interleukin-18 (IL-18) is a proinflammatory cytokine that plays an important role in chronic inflammation and autoimmune disorders. In this study, we aimed to determine the potential role of the IL18 gene in SLE. To define the genetic association of the IL18 and SLE, we have genotyped nine SNPs in an independent set of Spanish cases and controls. The IL18 polymorphisms were genotyped by PCR, using a predeveloped TaqMan allele discrimination assay. Two SNPs were still significant after fine mapping of the IL18 gene. The SNP (rs360719) surviving correction for multiple tests was genotyped in two replication cohorts from Italy and Argentina. After the analysis, a significance with rs360719 C-allele remained across the sets and after the meta-analysis (Pooled OR = 1.37, 95% CI 1.21-1.54, combined P = 3.8E-07, Pc = 1.16E-06). Quantitative real-time PCR was performed to assess IL18 mRNA expression in PBMC from subjects with different IL18 rs360719 genotypes. We tested the effect of the IL18 rs360719 polymorphism on the transcription of IL18 by electrophoretic mobility shift assay and western blot. We found a significant increase in the relative expression of IL18 mRNA in individuals carrying the rs360719 C-risk allele; in addition we show that the polymorphism creates a binding site for the transcriptional factor OCT-1. These findings suggest that the novel IL18 rs360719 variant may play an important role in determining the susceptibility to SLE and it could be a key factor in the expression of the IL18 gene.

Polymorphisms of CD16A and CD32 Fcγ receptors and circulating immune complexes in Ménière's disease: a case-control study.

BACKGROUND: Autoimmune diseases with elevated circulating autoantibodies drive tissue damage and the onset of disease. The Fcγ receptors bind IgG subtypes modulating the clearance of circulating immune complexes (CIC). The inner ear damage in Ménière's disease (MD) could be mediated by an immune response driven by CIC. We examined single-nucleotide polymorphism (SNPs) in the CD16A and CD32 genes in patients with MD which may determine a Fcγ receptor with lower binding to CIC. METHODS: The functional CD16A (FcγRIIIa*559A > C, rs396991) and CD32A (FcγRIIa*519A > G, rs1801274) SNPs were analyzed using PCR-based TaqMan Genotyping Assay in two cohorts of 156 mediterranean and 112 Galicia patients in a case-control study. Data were analyzed by χ2 with Fisher's exact test and Cochran-Armitage trend test (CATT). CIC were measured by ELISA for C1q-binding CIC. RESULTS: Elevated CIC were found in 7% of patients with MD during the intercrisis period. No differences were found in the allelic frequency for rs396991 or rs1801274 in controls subjects when they were compared with patients with MD from the same geographic area. However, the frequency of AA and AC genotypes of CD16A (rs396991) differed among mediterranean and Galicia controls (Fisher's test, corrected p = 6.9 × 10-4 for AA; corrected p = 0.02 for AC). Although genotype AC of the CD16A receptor was significantly more frequent in mediterranean controls than in patients, [Fisher's test corrected p = 0.02; OR = 0.63 (0.44-0.91)], a genetic additive effect for the allele C was not observed (CATT, p = 0.23). Moreover, no differences were found in genotype frequencies for rs396991 between patients with MD and controls from Galicia (CATT, p = 0.14). The allelic frequency of CD32 (rs1801274) was not different between patients and controls either in mediterranean (p = 0.51) or Galicia population (p = 0.11). CONCLUSIONS: Elevated CIC are not found in most of patients with MD. Functional polymorphisms of CD16A and CD32 genes are not associated with onset of MD.

Protection against anti-citrullinated protein antibody-positive rheumatoid arthritis is predominantly associated with HLA-DRB1*1301: a meta-analysis of HLA-DRB1 associations with anti-citrullinated protein antibody-positive and anti-citrullinated protein antibody-negative rheumatoid arthritis in four European populations.

OBJECTIVE: The protective effect of HLA-DRB1 alleles on the development of rheumatoid arthritis (RA) is poorly understood. The aim of this study was to perform a meta-analysis of 4 European populations to investigate which HLA-DRB1 alleles are associated with protection in anti-citrullinated protein antibody (ACPA)-positive RA and ACPA-negative RA. METHODS: Data for >2,800 patients and >3,000 control subjects for whom information on HLA-DRB1 typing and ACPA status was available were collected from 4 European countries: Norway, Sweden, The Netherlands, and Spain. The odds ratios (ORs) and 95% confidence intervals (95% CIs) associated with the different HLA-DRB1 alleles were analyzed in a combined meta-analysis focused on protective alleles and classifications. The analysis of ACPA-positive RA was stratified for the shared epitope (SE) alleles, to correct for skewing due to this association. RESULTS: In ACPA-positive RA, the only alleles that conveyed protection after stratification for SE were HLA-DRB1*13 alleles (OR 0.54 [95% CI 0.38-0.77]). The protective effect of the allele classifications based on the DERAA and D70 sequences was no longer present after exclusion of DRB1*13 (for D70, OR 0.97 [95% CI 0.75-1.25]), indicating that DRB1*13, rather than the DERAA or D70 sequence as such, is associated with protection. Among the DRB1*13 alleles, only DRB1*1301 was associated with protection (OR 0.24 [95% CI 0.09-0.59]). Protection appeared to follow a north-to-south gradient, with the strongest association in northern European countries. In ACPA-negative RA, there were no robust associations with HLA-DRB1 alleles. CONCLUSION: Our data do not support any of the classifications of protective alleles and indicate that protection against ACPA-positive RA is predominantly associated with HLA-DRB1*1301.

Novel association of the interleukin 2-interleukin 21 region with inflammatory bowel disease.

OBJECTIVES: Genome-wide association studies have reported the role of the interleukin (IL) 2-IL21 chromosomal region at 4q27 in several autoimmune conditions. Mice deficient in IL-2 develop a disease with clinical and histological similarity to ulcerative colitis (UC) in humans. Modest evidence of linkage with UC was tentatively proposed for the IL2 gene more than a decade ago. Therefore, we decide to investigate the association of polymorphisms in the IL-2 axis (IL2, IL2RA, and IL2RB genes) with inflammatory bowel diseases (IBDs). METHODS: Seven hundred and twenty-eight white Spanish unrelated IBD patients (356 Crohn's disease (CD) and 372 UC) and 549 ethnically matched controls were included in a case-control study. In addition, a Spanish replication cohort with 562 CD and 430 UC patients and 1,310 controls were analyzed. Eight single-nucleotide polymorphisms previously associated with different autoimmune diseases were analyzed using TaqMan chemistry. RESULTS: The IL2-rs6822844 polymorphism modified CD predisposition (P=0.002; odds ratio, OR (95% confidence interval, CI)=0.61 (0.44-0.84)); this was replicated in the other Spanish cohort, resulting in a strong protective effect of the minor allele in the merged samples (P=0.0002; OR (95% CI)=0.70 (0.58-0.85)). A similar effect of rs6822844 was detected for UC. Another marker, rs11938795, also showed evidence of an association with CD (P=0.006; OR (95% CI)=0.73 (0.58-0.92)). CONCLUSIONS: Polymorphisms within the IL2-IL21 linkage disequilibrium (LD) block show a novel association with IBD, this is concordant with suggestive previous results of whole genome analyses in CD and type 1 diabetes. Our data agree with the effect previously observed for other conditions and delineate a shared underlying mechanism.

Replication of an association between IL23R gene polymorphism with inflammatory bowel disease.

BACKGROUND & AIMS: Recently, the interleukin 23 receptor (IL23R) gene encoding a subunit of the receptor of the inflammatory cytokine IL-23 has been identified as a novel genetic factor strongly associated with inflammatory bowel disease (IBD). We aimed to replicate the IBD association of IL23R genetic markers in an IBD independent Spanish cohort. METHODS: Four hundred sixty IBD patients of Spanish white origin (238 CD and 222 UC) and 342 ethnically matched healthy controls comprised the study population. Eight single nucleotide polymorphisms (SNPs) spanning the IL23R gene and its downstream intergenic region were selected as genetic markers and genotyped by using Taqman 5' allelic discrimination assay. RESULTS: All genetic variants located within the IL23R gene were observed to confer a strong protective effect against IBD susceptibility in our population. The Arg381Gln (rs11209026) non-synonymous SNP was most significantly associated with IBD protection (odds ratio, 0.4; 95% confidence interval, 0.3-0.7). In addition to the single SNP analysis, we performed a haplotype analysis identifying 2 haplotypes significantly associated with IBD protection. CONCLUSIONS: In this study we replicate the association of IL23R genetic variants with IBD in a Spanish population. These findings, together with the previous results, suggest that the IL23R gene is one of the genetic factors implicated in the genetics of IBD in the general population.

CD209 in inflammatory bowel disease: a case-control study in the Spanish population.

BACKGROUND: The etiology of Ulcerative Colitis (UC) and Crohn's Disease (CD), considered together as Inflammatory Bowel Diseases (IBD), involves environmental and genetic factors. Although some genes are already known, the genetics underlying these diseases is complex and new candidates are continuously emerging. The CD209 gene is located in a region linked previously to IBD and a CD209 functional polymorphism (rs4804803) has been associated to other inflammatory conditions. Our aim was to study the potential involvement of this CD209 variant in IBD susceptibility. METHODS: We performed a case-control study with 515 CD patients, 497 UC patients and 731 healthy controls, all of them white Spaniards. Samples were typed for the CD209 single nucleotide polymorphism (SNP) rs4804803 by TaqMan technology. Frequency comparisons were performed using chi2 tests. RESULTS: No association between CD209 and UC or CD was observed initially. However, stratification of UC patients by HLA-DR3 status, a strong protective allele, showed that carriage of the CD209_G allele could increase susceptibility in the subgroup of HLA-DR3-positive individuals (p = 0.03 OR = 1.77 95% CI 1.04-3.02, vs. controls). CONCLUSION: A functional variant in the CD209 gene, rs4804803, does not seem to be influencing Crohn's disease susceptibility. However, it could be involved in the etiology or pathology of Ulcerative Colitis in HLA-DR3-positive individuals but further studies are necessary.

MYO9B gene polymorphisms are associated with autoimmune diseases in Spanish population.

The aim of the study was to test MYO9B gene polymorphisms for association with three autoimmune diseases, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and celiac disease (CD), in a Spanish population. We analyzed three SNPs (rs2305767, rs1457092, and rs2305764) in a case-control cohort composed of 349 SLE patients, 356 RA patients, 90 CD patients, and 345 healthy controls. All three SNPs showed a consistent increased frequency of the A allele in SLE, RA, and CD patients compared with healthy controls. An association was observed between CD and rs2305764 (p=0.01, OR=2.3), between SLE and rs1457092 (p=0.002, OR=1.4), and between RA and rs1457092 (p=0.02, OR=1.3). The three autoimmune diseases combined showed significant association with rs1457092 and rs2305764 and with the AAA haplotype (p haplotype=0.005, OR=1.3). Our data demonstrate consistent association with the A allele and AAA haplotype of three SNPs in the MYO9B gene, which were previously reported to be associated with CD in the Dutch population. This suggests that genetic variation in MYO9B is associated with CD, SLE, and RA and that MYO9B is a general risk factor for autoimmunity.

HLA-DRB1*1101 allele may be associated with bilateral Méniére's disease in southern European population.

OBJECTIVE: To analyze the associations of HLA-DRB1* and DQB1* Class II alleles in patients with bilateral Méniére's disease (MD). PATIENTS AND METHODS: Eighty patients from two ethnically defined groups with definite bilateral MD, according to the diagnostic scale of the American Academy of Otolaryngology-Head and Neck Surgery, were compared with normal controls from the same origin in a prospective multicenter study. We performed an allele-specific amplification for HLA-DRB1* and DQB1* genes of the major histocompatibility complex. RESULTS: The allele HLA-DRB1*1101 was associated with bilateral MD in the Mediterranean population (odds ratio, 3.65 [95% confidence intervals, 1.5-9.1], corrected p = 0.029); however, this allele was not associated in the group from Galicia (northwest of Spain). No differences were found in the distribution of alleles for the gene HLA-DQB1* between patients and controls. CONCLUSION: The allele HLA-DRB1*1101 and the allelic group HLA-DRB1*11 may determine an increased susceptibility to develop bilateral MD in a southern European population.

Interleukin 12 (IL12B) and interleukin 12 receptor (IL12RB1) gene polymorphisms in rheumatoid arthritis.

The aim of this study was to assess the possible association between the IL12B and the IL12RB1 gene polymorphisms and the systemic autoimmune disease rheumatoid arthritis (RA). Our study population consisted of 545 patients with RA and 393 healthy subjects. All the individuals were of white Spanish origin. Genotyping of the IL12B (IL12Bpro and IL12B 3' untranslated region) and IL12RB1 (641A-->G, 1094T-->C, and 1132G-->C) polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism and polymerase chain reaction-fluorescent methods. No statistically significant differences in the distribution of the IL12B and the IL12RB1 genotypes and alleles between patients with RA and control subjects were observed. In addition, no association was found between the above-mentioned polymorphisms with any of the demographic and clinical parameters tested in patients with RA. These results suggest that IL12B and IL12RB1 genes may not play a relevant role in the susceptibility or severity of RA in the Spanish population.

Analysis of a GT microsatellite in the promoter of the foxp3/scurfin gene in autoimmune diseases.

The aim of this study was to assess the possible association of the functional (GT)(n) microsatellite polymorphism in the FOXP3 gene with predisposition to several autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), ulcerative colitis (UC), Crohn's disease, and celiac disease. We analyzed a case-control cohort composed of 231 SLE patients, 293 RA patients, 528 inflammatory bowel disease (354 Crohn's disease patients and 260 UC patients) patients, 103 celiac disease patients, and 274 healthy controls ethnically matched. Genotyping of (GT)(n) microsatellite was performed by polymerase chain reaction (PCR)-based method combined with fluorescent technology. We found no evidence for association of this polymorphism between controls and these autoimmune disease patients. Additionally, no differences in the genotype and allele distribution were found when patients were stratified according to clinical manifestation. The (GT)(n) microsatellite of the FOXP3 gene may not play a relevant role in the susceptibility to SLE, RA, inflammatory bowel disease, and celiac disease in our population.

Analysis of a functional BTNL2 polymorphism in type 1 diabetes, rheumatoid arthritis, and systemic lupus erythematosus.

The aim of this study was to test whether the functional variant rs2076530 of the BTNL2 gene confers susceptibility to the autoimmune diseases type 1 diabetes (T1D), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE). Our study populations consisted of 326 patients with T1D and 351 healthy subjects, 808 patients with RA and 1137 healthy controls, and 372 patients with SLE and 280 healthy controls. Genotyping of the BTNL2 gene rs2076530 polymorphism was performed by real-time polymerase chain reaction technology, using the TaqMan 5'-allele discrimination assay. We observed statistically significant differences in the distribution of BTNL2rs2076530 alleles between patients with T1D, RA, and SLE and healthy controls (p=0.0035, 0.000003, and 0.00002, respectively), but in two divergent ways: the G allele was associated with T1D and RA, and the A allele was associated with SLE. However, the polymorphism exhibited strong linkage disequilibrium with HLA DQB1-DRB1 haplotypes previously identified as predisposing to the diseases. When the BTNL2 polymorphism was tested conditional on HLA DQB1-DRB1haplotypes, the BTNL2 effect was no longer significant in all three study populations. The BTNL2 rs2076530 polymorphism is associated with T1D, RA, and SLE because of its strong linkage disequalibrium with predisposing HLA DQB1-DRB1 haplotypes in Caucasian populations.

A functional polymorphism of the NFKB1 promoter is not associated with ulcerative colitis in a Spanish population.

BACKGROUND: This study investigated the influence of the NFKB1-94ins/delATTG in the susceptibility/phenotype to ulcerative colitis. METHODS: We analyzed the distribution of -94ins/delATTG NFKB1 in 258 patients and 264 healthy controls from southern Spain by a polymerase chain reaction-fluorescent method. RESULTS: The genotype and allele frequencies of -94ins/delATTG did not significantly differ between patients and controls. In fact, the frequency of the -94delATTG allele was almost identical in both groups (34.8% and 35.4%, respectively), and the del/del genotype was underrepresented in UC patients (11.2% versus 14%). In addition, no association of this polymorphism was found with any of the clinical parameters analyzed. CONCLUSION: These results suggest that the NFKB1 -94ins/delATTG gene variation, previously associated with UC susceptibility in North Americans, does not influence either susceptibility or phenotype of UC in the Spanish population.

Human leukocyte antigen-DQB1 and -DRB1 associations in patients with idiopathic sudden sensorineural hearing loss from a defined population of Northwest Spain.

CONCLUSION: The results of this study support the assertion that Southern European individuals have a genetically mediated predisposition to develop idiopathic sudden sensorineural hearing loss (SNHL). OBJECTIVE: To assess the influence of human leukocyte antigen (HLA)-DQB1 and -DRB1 alleles on the susceptibility to and the severity of idiopathic sudden SNHL. MATERIAL AND METHODS: A prospective study of patients diagnosed with idiopathic sudden SNHL between October 2000 and September 2002 was conducted. Patients were included in the study if they were diagnosed with idiopathic sudden SNHL within 1 week after the onset of deafness symptoms and had been followed for at least 12 months. HLA-DQB1 and -DRB1 typing was performed from DNA using molecular-based methods on patients and ethnically matched healthy controls. RESULTS: Thirty-three patients fulfilled the inclusion criteria. No significant differences in HLA-DQB1 phenotype frequencies were found between patients and controls (n = 145). Carriage of HLA-DRB1*0403 was significantly increased in the whole group of patients compared with controls (OR = 11.97; 95% CI 1.99-91.60; p = 0.002; p(corr) = 0.04). In patients without auditory improvement the frequency of the HLA-DRB1*04 phenotype was significantly increased compared with healthy controls (OR = 6.57; 95% CI 1.62-26.70; p = 0.003; p(corr) = 0.04).

Absence of COCH mutations in patients with Meniere disease.

Missense mutations in the coagulation factor C homology (COCH) gene (14q12-q13) cause the autosomal dominant sensorineural hearing loss and vestibular disorder DFNA9 (OMIM 603196), and a high prevalence of symptoms of Meniere disease (MD) has been described in families with a mutation in the COCH gene. In this study, we search for mutations in the COCH gene in peripheral blood from patients with definite MD. DNA was extracted from peripheral blood cells of 30 individuals with MD and 30 controls. Exons 4 and 5 of the COCH gene were amplified by PCR reaction, using primer pairs flanking both exons. Sequences were analysed by a DNA sequencing system and compared with the published COCH cDNA sequence. No differences were found in the nucleotide sequences of exons 4 and 5 in the COCH gene in patients with definite sporadic MD when they were compared with the control group. Patients with definite MD have a low prevalence of mutations in exons 4 and 5 of the COCH gene.