Study of the role of a functional polymorphism of MHC2TA in rheumatoid arthritis in three ethnically different populations.
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Arthritis, Rheumatoid↗
Biomedical subjects
A Balsa
Publications and source records attributed to A Balsa.
Asporin repeat polymorphism in rheumatoid arthritis.
BACKGROUND: Asporin belongs to a family of proteins associated with the cartilage matrix. OBJECTIVE: To investigate the role of the functional polymorphism consisting of an aspartic acid (D) repeat polymorphism located in the ASPN gene in the susceptibility to and clinical outcome of rheumatoid arthritis. METHODS: A total of 803 Spanish Caucasian patients with rheumatoid arthritis and 904 controls of the same ethnic origin and matched for age and sex were included in the study. The asporin D repeat polymorphism was genotyped using polymerase chain reaction with a fluorescent primer. RESULTS: No significant differences were detected in the distribution of the 10 alleles found in our population on comparing patients with rheumatoid arthritis with control groups. Nevertheless, individuals bearing D14 produced rheumatoid factor more often than the rest (85.7% v 72.1%, p = 0.006, odds ratio (OR) = 2.35, 95% confidence interval 1.21 to 4.50), and the mean (SD) onset age was higher in the group of individuals bearing D13 (50.09 (13.94)) compared with the rest (47.21 (14.31)), although the difference did not reach significance (p = 0.06). CONCLUSION: The results do not support a major role for asporin D repeat polymorphism in the susceptibility to rheumatoid arthritis. Nevertheless, they support the influence of this gene on the outcome of the disease.
Adult↗
Epistatic interaction between FCRL3 and NFkappaB1 genes in Spanish patients with rheumatoid arthritis.
BACKGROUND: A Japanese study has described a strong association between rheumatoid arthritis and several polymorphisms located in the Fc receptor-like 3 (FCRL3) gene, a member of a family of genes related to Fc receptors located on chromosome 1q21-23. OBJECTIVES: To evaluate the association between rheumatoid arthritis and FCLR3 polymorphisms in a large cohort of Caucasian patients with rheumatoid arthritis and healthy controls of Spanish origin. Owing to the described functional link between the FCRL3 polymorphisms and the transcription factor nuclear factor kappaB (NFkappaB), a functional polymorphism located in the NFkappaB1 gene was included. METHODS: 734 patients with rheumatoid arthritis from Madrid and Granada, Spain, were included in the study, along with 736 healthy controls. Polymorphisms in the FCRL3 gene were studied by TaqMan technology. The -94ins/delATTG NFkappaB1 promoter polymorphism was analysed by fragment analysis after polymerase chain reaction with labelled primers. Genotypes were compared using 3x2 contingency tables and chi2 values. RESULTS: No overall differences were found in any of the FCRL3 polymorphisms and in the NFkappaB1 promoter polymorphism when patients were compared with controls. However, when stratified according to NFkappaB1 genotypes, a susceptibility effect of FCRL3 polymorphisms was observed in patients who were heterozygotes for NFkappaB1 (pc = 0.003). CONCLUSIONS: The FCRL3 polymorphisms associated with rheumatoid arthritis in a Japanese population are not associated per se with rheumatoid arthritis in a Spanish population. A genetic interaction was found between NFkappaB1 and FCRL3 in Spanish patients with rheumatoid arthritis. These findings may provide a general rationale for divergent genetic association results in different populations.
Adult↗
PADI4 polymorphisms are not associated with rheumatoid arthritis in the Spanish population.
OBJECTIVES: The presence of anti-citrullinated peptide antibodies is the most specific serological marker known of rheumatoid arthritis (RA). The PADI4 gene, encoding a haematopoietic isoform of the peptidylarginine deiminase citrullinating enzyme, has recently been associated with susceptibility to RA in the Japanese population. A subsequent UK report could not confirm this association, and a later French study also yielded a negative result. Given this discrepancy and the importance of antibodies against citrullinated peptides in the early course of the disease, we performed a replication study. METHODS: Three hundred and fifty-four Spanish RA patients and 498 Spanish controls were recruited from two Madrid hospitals. The padi4_104 and padi4_94 single-nucleotide polymorphisms (SNP) were analysed by TaqMan assays. RESULTS: Similarly to what was described in the British and French population, the less frequent allele of this SNP was not associated with the disease (genotype TT, 16.1% in RA patients vs 14.3% in controls; P = 0.46, odds ratio 1.15, 95% confidence interval 0.78-1.71). A confirmatory negative result was obtained on analysing another SNP in the same gene, padi4_94, in 248 RA patients and 394 controls. CONCLUSIONS: The results of our group and from the British and French studies strongly suggest that polymorphisms of the PADI4 gene do not play a role in susceptibility to RA in European populations.
Adult↗
A poly(ADP-ribose) polymerase haplotype spanning the promoter region confers susceptibility to rheumatoid arthritis.
OBJECTIVE: To investigate the association of the poly(ADP-ribose) polymerase 1 (PARP-1) gene promoter polymorphism with rheumatoid arthritis (RA) predisposition. METHODS: An association study with 213 Spanish RA patients and 242 healthy subjects was carried out to investigate the association of all known PARP-1 gene promoter polymorphisms, i.e., a CA microsatellite repeat, a poly(A)(n), and 3 single point mutations (C410T, C1362T, and G1672A), with disease susceptibility. Additionally, we analyzed the distribution of PARP-1 polymorphisms in 58 Spanish families with 1 or more affected members. RESULTS: Upon complete genotyping of the panel of 455 samples, strong linkage disequilibrium was observed among the 5 PARP-1 polymorphisms. Only 2 PARP-1 haplotypes were detected: haplotype A (410T-[A](10)-[CA](10-12)-1362C, which includes short PARP-1 CA alleles) and haplotype B (410C-[A](11)-[CA](13-20)-1362T, always paired with long PARP-1 CA variants). Regarding the G1672A variation, although linkage disequilibrium was detected, it did not seem to be part of the conserved haplotypes described. Haplotype B was statistically overrepresented in the RA patient group compared with the healthy subjects (odds ratio 1.42, 95% confidence interval 1.06-1.91, P = 0.019). In addition, a significant dose effect of PARP-1 haplotype carriage on disease predisposition was observed. Of note, within haplotype B, the PARP-1 CA 97-bp allele was found to be the RA-predisposing marker (odds ratio 2.17, 95% confidence interval 1.27-3.72, P = 0.003, corrected P < 0.05). CONCLUSION: Our results demonstrate the existence of 2 unique PARP-1 haplotypes in the Spanish population and provide the first evidence that PARP-1 haplotypes play a role in susceptibility to RA.
Arthritis, Rheumatoid↗
Genetic polymorphisms in Spanish rheumatoid arthritis patients: an association and linkage study.
HLA polymorphism accounts only for approximately one-third of the genetic predisposition to rheumatoid arthritis (RA). To investigate the role of other loci in the susceptibility to RA, we have performed an analysis of several polymorphisms in genes of immune-related function: IL-10 -1082, -819, -592 promoter single nucleotide polymorphisms (SNPs), IL-10G and IL-10R microsatellites, IL-6 -622 promoter SNP, FcgammaRIIIA Val/Phe-158 polymorphism, IL-1 receptor antagonist VNTR, and the IKBL+738 T/C mutation. The analysis has been performed on a case-control study and also on RA trios. IL-10G12 was found to be associated with RA in the case-control study (18% in RA patients vs 9% in controls: P=0.001; pc<0.05). This allele was also more often transmitted than not transmitted (10 vs 5). No other allele in the present study is found to be associated to RA. Our data suggest that most of the loci studied play no major role in the susceptibility to RA, the IL-10 gene being the sole exception.
Arthritis, Rheumatoid↗
Rheumatoid arthritis in Spain: occurrence of extra-articular manifestations and estimates of disease severity.
OBJECTIVES: To characterise RA in a sample of Spanish patients by estimating mean clinical activity, functional ability, and radiological damage, and current and cumulative prevalence of extra-articular manifestations. METHODS: Cross sectional analysis of a cohort of patients with RA randomly selected from the clinical databases of 34 centres. Standard definitions and measurements were used, and radiographs read centrally. Estimates and confidence intervals were adjusted to sampling. RESULTS: Data were available for 788 patients. Extra-articular RA was present in 285 (36.2%) patients. Cumulative prevalence and 95% confidence intervals of extra-articular manifestations were estimated: nodules 24.5% (21.5 to 27.5), Sjögren's syndrome 17.0% (14.4 to 19.6), atlantoaxial subluxation 12.1% (9.8 to 14.4), carpal tunnel syndrome 10.7% (7.8 to 13.6), interstitial lung disease 3.7% (2.4 to 5.0), serositis 2.5% (1.4 to 3.5), eye disease 2.5% (1.1 to 3.9), vasculitis 1.3% (0.5 to 2.1), amyloidosis 0.6% (0.1 to 1.2), and Felty's syndrome 0.3% (<0.6). Mean (SD) activity/progression indexes were: DAS28-3 3.4 (1.2), HAQ 1.6 (0.4), Larsen score 54.7 (26.4). Less than 5% of the patients were in remission. 205 (72%) patients were receiving disease modifying antirheumatic drugs (DMARDs). CONCLUSION: Spanish patients with RA ever seen by a rheumatologist have, on average, a moderate degree of activity, despite widespread use of DMARDs. Measures of the degree of progression do not show a benign disease. The proportion of extra-articular manifestations in Spanish patients with RA is similar to that found in other Mediterranean populations, and lower than that reported in Anglo Saxon countries.
Adult↗
Genetic determinants of rheumatoid arthritis: the inducible nitric oxide synthase (NOS2) gene promoter polymorphism.
An association study and a linkage analysis were carried out in parallel in order to investigate the association of the inducible nitric oxide synthase (NOS2) gene promoter polymorphism with rheumatoid arthritis (RA) predisposition and/or outcome including a -954G-C mutation, a di-allelic (TAAA)(n) marker and the highly polymorphic (CCTTT). The -954G-C point mutation occurred non-polymorphic and the di-allelic (TAAA)(n) marker was not associated with RA predisposition. The (CCTTT)(n)locus showed a trend for RA association in the case-control study, however, stratification data by Class II status did not yield significant effect and overall, the family study showed no significant association nor linkage for any of the markers under study using TDT and non-parametric linkage respectively. Finally, no influence was detected regarding any of the clinical parameters tested. After evaluating for the first time the influence of NOS2 promoter polymorphism in RA, it seems to have no major effect on disease susceptibility and/or outcome.
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Factors related to radiological damage in 61 Spaniards with early rheumatoid arthritis.
OBJECTIVE: To determine whether the presence of radiographic erosions at disease onset in patients with early rheumatoid arthritis (RA) is associated with clinical, serological, or genetic factors of poor outcome and whether patients with erosions only in the feet have a different pattern of presentation. METHODS: Sixty one patients with early RA (<6 months of evolution) were studied. Clinical evaluation and serological, radiological, and genetic studies were performed at disease onset and after one year. RESULTS: Forty one (67%) patients showed erosions in their hands or in their feet, or in both. Subjects with erosive RA had a higher number of swollen joints (SJN; 9 (SD 6) v. 6 (3), p=0.008), and rheumatoid factor (RF) positivity was more common (80% v. 50%, p<0.02) than those without erosions. Seven (17%) of the 41 patients in the group with erosions had erosions only in their feet. This group had a longer duration of morning stiffness (120 (60) v. 72 (52) min, p<0.005), better patient's global assessment of general health (34 (22) v. 57 (25), p< 0.05), and lower erythrocyte sedimentation rate (32 (22) v. 60 (30) mm/1st h, p <0.05) than the rest of the subjects with erosions, and none of them was in remission after one year. Remission after one year was related to a lack of cortical damage at onset and RF negativity. CONCLUSIONS: Radiological damage at disease onset is associated with a worse clinical presentation and RF positivity, which are markers of poor outcome. There is a subgroup of patients, with erosions only in their feet, whose clinical presentation is less aggressive. To identify these cases of early erosive RA, radiographs of the feet should be obtained routinely.
Adult↗
Primary association of a MICA allele with protection against rheumatoid arthritis.
OBJECTIVE: To determine whether major histocompatibility complex class I chain-related gene A (MICA) polymorphisms are associated with susceptibility to rheumatoid arthritis (RA) independently of the HLA-DRB1 shared epitope (SE). METHODS: Fifty-four Spanish families with an affected son or daughter and 211 consecutive RA patients were genotyped for HLA-DRB1, tumor necrosis factor a/b microsatellite alleles, and MICA transmembrane polymorphism. We performed a case-control comparison with the consecutive patients and an independent transmission disequilibrium test with the families. RESULTS: The frequency of the MICA 6.0 allele was significantly reduced, compared with controls, in the group of SE+ patients (odds ratio 0.39, P = 0.0005). Additionally, the haplotypes containing this allele were preferentially not transmitted to the affected offspring (9 transmitted of 33; P = 0.007), independent of the presence or absence of an SE either in the same haplotype or in the other haplotype in the progenitor. CONCLUSION: These data suggest that the MICA 6.0 allele is an independent marker of protection against RA in the SE+ group of RA patients.
Adult↗
Clinical and immunogenetic characteristics of European multicase rheumatoid arthritis families.
OBJECTIVE: To describe the characteristics of a new set of European families with affected sib pairs (ASP) collected by the European Consortium on Rheumatoid Arthritis Families (ECRAF) to replicate the results of our first genome scan. Potential gradients for disease severity in Europe and concordance within families were studied. PATIENTS AND METHODS: From 1996 to 1998 European white families with at least two affected siblings were enrolled in the study. Demographic (sex, age at onset), clinical data (rheumatoid factor (RF), disease duration, erosive disease, extra-articular features (EF)), and HLA-DRB1 oligotyping were analysed. RESULTS: 565 patients with rheumatoid arthritis (RA), belonging to 271 families including 319 affected sib pairs (ASP) were collected. Belgium, France, Italy, the Netherlands, Portugal, and Spain contributed 20, 96, 52, 24, 9, and 70 families, respectively. Sex (78% women), age at onset (mean 44 years), and RF positivity (79%) were similar among the countries. Differences were found in disease duration (11-18 years) and in the prevalence of erosive disease (70-93%), nodules (15-44%), subjective Sjögren's syndrome (5-38%), and EF (3-16%) (p<0.05 in all cases). A total of 22% RA sibs were shared epitope (SE) negative, whereas 47% and 30% carried one and two SE alleles respectively. Carriage of SE differed widely among countries (p<0.0001): no SE alleles (6-36%), one allele (43-60%), and two alleles (20-39%). SE encoding alleles were mainly DRB1*04 in the Netherlands and Belgium, whereas SE carriage was less common and evenly distributed between DRB1*01, *04, and *10 in Mediterranean countries. No concordance within families was found either in age/calendar year of onset (intraclass correlation coefficient <0.50) or in clinical and radiological features (kappa<0.22). CONCLUSIONS: The differences in RA characteristics between European countries and within families underline the heterogeneity of the disease. No clear cut gradient of disease severity was seen in Europe.
Adult↗
Noninherited maternal antigens do not increase the susceptibility for familial rheumatoid arthritis. European Consortium on Rheumatoid Arthritis Families (ECRAF).
OBJECTIVE: It has been proposed that noninherited maternal HLA-DR antigens (NIMA) might play a role in the susceptibility for rheumatoid arthritis (RA). This hypothesis has not been thoroughly tested in patients with familial RA, in whom genetic factors, either inherited or not, might have stronger influence than in patients with sporadic RA. We investigated the NIMA hypothesis in a large cohort of European patients with familial RA. METHODS: The distribution of NIMA, noninherited paternal antigens (NIPA), and inherited HLA-DR antigens was assessed in patients with familial RA from all family sets collected from 1996 onwards by the ECRAF. HLA-DRB1 oligotyping from patients and all available nonaffected siblings and parents was carried out. Familial RA was defined by the presence of at least 2 affected first-degree relatives in the same family. The frequencies of HLA-DR NIMA and NIPA were compared using odds ratios after stratification for HLA-DR*04, *0401, and/or *0404 and shared epitope (SE) status. NIMA/NIPA that coincided with inherited parental HLA-DR antigens were considered redundant and were excluded from analysis. RESULTS: NIMA and NIPA could be analyzed in 165 RA patients with familial RA and 84 nonaffected siblings. Patients were predominantly female, rheumatoid factor positive, and had erosive disease (81, 75, and 84%, respectively). Possession of HLA-DR*04 and *0401/*0404 alleles tended be more frequent in patients than in nonaffected siblings but this did not reach statistical significance. SE possession was similar in patients and healthy siblings, although the former had a double dose SE more often (37.6 vs 17.8%; p = 0.002). Transmission of SE encoding alleles from parents to offspring was skewed only in patients [OR (95% CI) 3.56 (2.55-4.95) vs 1.16 (0.75-1.79) in nonaffected siblings]. Using the NIPA as control, the frequencies of HLA-DRB1*04, *0401/*0404, and SE positive NIMA were not increased in patients lacking these susceptibility alleles. The frequencies of NIMA encoding susceptibility alleles in DR*04 and *0401/*0404 negative patients were lower than in nonaffected siblings. CONCLUSION: Our results corroborate the association between RA and inherited SE alleles and do not support a role for noninherited HLA-DR maternal antigens in the susceptibility for familial RA.
Adult↗
[Clinical characteristics of familial rheumatoid arthritis in Spain. A study of 73 families. Spanish Consortium for Rheumatoid Arthritis (CEAR) and European Consortium for Familial Rheumatoid Arthritis (ECRAF)].
OBJECTIVE: To describe clinical characteristics and the homogeneity of disease expression between involved members in multicase Spanish rheumatoid arthritis (RA) families. PATIENTS AND METHODS: 73 families with two or more siblings with RA were found, with a total of 149 patients distributed in 79 pairs (70 sib pairs, and 3 sib trios). Demographic, clinical and radiological characteristics were recorded in a standard questionnaire. RESULTS: Clinical characteristics were similar to those of sporadic RA with a high frequency of women (78%), positive rheumatoid factor (RF) (86%), erosions (89%) and a 25% of the patients having extraarticular disease. The most important variable in disease severity was disease duration. The concordance between family members of the same age and calendar year of disease onset, and the pattern of disease expression, was not higher than expected, showing that the disease is heterogenic. CONCLUSION: Environmental factors seem to be more important in RA susceptibility. Clinical characteristics of familiar RA in Spain do not seem to be different from sporadic RA, although differences were found in disease expression within families that may be due to variation of genetic or environmental factors, responsible for the susceptibility and disease duration.
Adult↗
Noninherited maternal antigens do not play a role in rheumatoid arthritis susceptibility in Europe. European Consortium on Rheumatoid Arthritis Families.
OBJECTIVE: It has been proposed that noninherited maternal antigens (NIMA) (HLA-DR antigens) might play a role in susceptibility to rheumatoid arthritis (RA), especially in patients who are not genetically predisposed, such as those who are HLA-DR4 and/or shared epitope (SE) negative. The present study was undertaken to test the NIMA hypothesis in a large cohort of European RA patients assembled by the European Consortium on RA Families (ECRAF). METHODS: HLA-DRB1 oligotyping was performed in families of European RA patients for whom both parents were alive. These families were consecutively recruited by the ECRAF between 1996 and 1998, for association studies. The frequencies of HLA-DR NIMA were compared with those of the noninherited paternal antigens (NIPA) after stratification for HLA-DR*04, *0401 and/or *0404, and SE status. NIMA or NIPA that coincided with inherited HLA-DR antigens were considered redundant and excluded from analysis. Calculations concerning the whole group and restricted to patients lacking parental RA were performed. RESULTS: One hundred seventy families from France (n = 81), Belgium (n = 23), Spain (n = 24), Italy (n = 19), Portugal (n = 14), and The Netherlands (n = 9) were oligotyped. The group of probands was predominantly female (88%), positive for rheumatoid factor, DR*04, and SE (71%, 58%, and 75%, respectively), and had erosive disease (75%). Parental RA was reported in 21 families. Using the NIPA as control, the frequency of HLA-DRB1*04, *0401 and/or *0404-, or SE-positive NIMA was not found to be increased in patients lacking these susceptibility alleles. The same was true when the 21 probands with parental RA were excluded from analysis. In DRB1*04-positive patients, we found no evidence of a relevant effect of HLA-DR3 or DR6 in the NIMA. CONCLUSION: Our results do not support the notion that noninherited maternal antigens have a role in susceptibility to RA in the offspring.
Adult↗
Primary association of tumor necrosis factor-region genetic markers with susceptibility to rheumatoid arthritis.
OBJECTIVE: To determine whether tumor necrosis factor (TNF) polymorphisms are associated with susceptibility to rheumatoid arthritis (RA) independently of the HLA-DR shared epitope. METHODS: Fifty-two Spanish families with one or more affected members were typed for HLA-DRB1, TNF promoter polymorphisms, and TNFa and TNFb microsatellites. We performed an association analysis comparing transmitted versus not transmitted haplotypes, with or without shared epitope, to determine whether there is an independent effect of TNF genetic markers on RA susceptibility. RESULTS: TNFa6,b5 was significantly associated with susceptibility to RA. The haplotypes containing these markers were preferentially transmitted to the affected offspring, even if these haplotypes lacked the HLA-DR shared epitope. TNF promoter polymorphisms were not associated with susceptibility to RA. CONCLUSION: The data suggest that TNFa/b is an independent marker of RA susceptibility, pointing to a genetic role of the TNF region in the pathogenesis of RA.
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IL-6 promoter polymorphisms in rheumatoid arthritis.
We investigated the possible association between the IL-6 promoter polymorphisms, at positions -622 and -174, and susceptiblity to, and/or outcome of, rheumatoid arthritis (RA). A total of 163 patients with RA and 157 healthy controls were genotyped for IL-6 using a PCR-RFLP method. The -622 and -174 alleles were in complete linkage disequilibrium. No difference was observed in the distribution of IL-6 promoter genotype or allele frequencies between RA patients and controls. However, a significant difference in the mean age at disease onset between IL-6 genotypes was observed. The present data appear to rule out an important role of IL-6 promoter polymorphisms in the susceptibility to RA. However, IL-6 genotypes may contribute to the pathogenesis of the disease by influencing the age at disease onset.
Adult↗
Pes anserinus tendino-bursitis: what are we talking about?
We studied the ultrasonographic (US) features of the pes anserinus insersion (PA) and subcutaneous medial knee fat in patients clinically diagnosed of pes anserinus tendino-bursitis (PATB) syndrome. Thirty seven consecutive patients with suspected PATB were clinically evaluated and their knees examined using a 7.5 MHz linear probe. In twenty-three patients with unilateral clinical PATB (group A) the painful knee was compared with their painless opposite knee. Six patients with bilateral clinical PATB (group B) were compared with 6 healthy controls (group C). All patients were women with radiographic knee osteoarthritis in 93% and body mass index > 27 in 75%. US pes anserinus tendinitis was found in one symptomatic knee and pes anserinus bursitis in two symptomatic knees and in one asymptomatic knee. No US signs of panniculitis were found in patients and controls. In conclusion, patients diagnosed of PATB syndrome in rheumatology rarely have US tendinitis or bursitis of the PA.
Aged↗
Class II MHC antigens in early rheumatoid arthritis in Bath (UK) and Madrid (Spain).
OBJECTIVE: A number of studies have indicated that rheumatoid arthritis (RA) is a less severe disease in Mediterranean countries than in Northern Europe. We investigated whether differences in the frequency of class II MHC antigens might contribute to this variation in disease severity. METHODS: Typing at HLA-DR and -DQ loci was carried out at low and high resolutions by polymerase chain reaction amplification in patients with early RA of less than 6 months' duration (68 patients in Madrid and 68 in Bath) and in control subjects (929 in Madrid and 226 in Bath). Only ethnic Spanish and British individuals were included as patients and controls. RESULTS: Shared epitope (SE) alleles represented 19.8 and 28.9% of the total number of class II MHC alleles in controls from Madrid and Bath respectively (P: = 0.00001), this difference being largely due to increased numbers of DRB1*0401 individuals in the British subjects (P: = 0.0000001). Analysis of the patients showed the expected increase in SE alleles when compared with their respective control groups (Madrid, 31.6 vs 19.8%; Bath, 42.6 vs 28. 9%). In Bath the SE was mainly encoded by HLA-DR4 alleles (74.1%), while in Madrid it was encoded almost equally by DR4 (51.1%) and DR1 (44.7%) alleles. The risk of developing RA in carriers of SE alleles was similar in the two cities (Bath, odds ratio 1.83, 95% confidence interval 1.23-2.78; Madrid, odds ratio 1.87, 95% confidence interval 1.25-2.77), and was largely accounted for by HLA-DRB1*0401 alleles. CONCLUSION: We conclude that rheumatoid patients in Bath differ from their Spanish counterparts in class II antigen expression and allele frequency. This may be explained partly by genetic differences between the control populations in the two centres, and may help to explain the greater incidence of more severe rheumatoid disease expression seen in RA patients in the UK.
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