HLA-B*57 and IFNL4-related polymorphisms are associated with protection against HIV-1 disease progression in controllers.

Background: HIV-1-controllers maintain HIV-1 viremia at low levels (normally <2000 HIV-RNA copies/mL) without antiretroviral treatment. However, some HIV-1-controllers have evidence of immunologic progression with marked CD4+T-cell decline. We investigated host genetic factors associated with protection against CD4+T-cell loss in HIV-1-controllers. Methods: We analysed the association of interferon lambda 4 (IFNL4)-related polymorphisms and HLA-B haplotypes within Long Term Non-Progressor HIV-1-controllers ((LTNP-C), defined by maintaining CD4+T-cells counts >500 cells/mm3 for more than 7 years after HIV-1 diagnosis) versus non-LTNP-C, who developed CD4+T-cells counts <500 cells/mm3 Both a Spanish study cohort (n=140) and an international validation cohort (n=914) were examined. Additionally, in a subgroup of individuals HIV-1-specific T-cell responses and soluble cytokines were analysed RESULTS: HLA-B*57 was independently associated with the LTNP-C phenotype (OR=3.056 (1.029-9.069) p=0.044 and OR=1.924 (1.252-2.957) p=0.003) while IFNL4 genotypes represented independent factors for becoming non-LTNP-C (TT/TT, ss469415590, OR=0.401 (0.171-0.942) p=0.036 or A/A, rs12980275, OR=0.637 (0.434-0.934) p=0.021) in the Spanish and validation cohort, respectively, after adjusting for sex, age at HIV-1 diagnosis, IFNL4-related polymorphisms and different HLA-B haplotypes. LTNP-C showed lower plasma IP-10 (p=0.019) and higher IFN-γ (p=0.02) levels than the HIV-1-controllers with diminished CD4+T-cell numbers. Moreover, LTNP-C exhibited higher quantities of IL2+CD57- and IFN-γ+CD57- HIV-1-specific CD8+T-cells (p=0.002 and 0.041, respectively) than non-LTNP-C. Conclusions: We have defined genetic markers able to segregate stable HIV-1-controllers from those who experience CD4+T-cell decline. These findings allow for identification of HIV-1-controllers at risk for immunologic progression, and provide avenues for personalized therapeutic interventions and precision medicine for optimizing clinical care of these individuals.

Fine-mapping butyrophilin family genes revealed several polymorphisms influencing viral genotype selection in hepatitis C infection.

Host-viral genetic interaction has a key role in hepatitis C infection (HCV) and maybe in the viral selection. In a preliminary GWAS analysis, we identified BTN3A2 rs9104 to be associated with HCV genotype 1. Therefore, our aim was to determine the influence of BTN family on the selection of HCV genotype. We performed a fine-mapping analysis of BTN gene region in a cohort of chronic HCV infection (N=841), validating significant results in another independent chronic HCV infection cohort (N=637), according to selection of viral genotype. BTN3A2 rs9104, BTN3A2 rs733528, BTN2A1 rs6929846, BTN2A1 rs7763910 and BTN3A3 rs13220495 were associated with viral genotype selection. Interestingly, BTN3A2 rs9104 GG genotype was closely related to genotype 1 infection (80.7% (394/488) compared with genotype 3 infection (53.5% (23/43); P=0.0001) in patients harboring IL28B-CT/TT genotype, although this effect was not observed in IL28B-CC genotype. Similarly, BTN3A3 rs13220495 CC genotype was linked to genotype 3 infection (100% (32/32)) compared to genotype 1 (87.3% (137/157); P=0.028) in patients harboring IL28B-CC genotype, but did not in IL28B-CT/TT genotype. Genetic variants in the butyrophilin family genes may alter susceptibility to infection, selecting HCV genotype and influencing disease progression. BTN3A2 rs9104 was strongly associated with genotype 1 infection and the haplotype BTN3A3 rs13220495 CC+IL28B genotype CC was universal in patients with hepatitis C genotype 3a.

Differential expression pattern of microRNAs in CD4+ and CD19+ cells from asymptomatic patients with systemic lupus erythematosus.

OBJECTIVE: The aim of this study was to investigate the pattern of microRNA (miRNA) expression in CD19+ and CD4+ cells from asymptomatic patients with systemic lupus erythematosus (SLE). METHODS: A screening of the expression of 377 miRNAs was performed in human CD4+ and CD19+ cells isolated from the peripheral blood by using a TaqMan Human MicroRNA Array. Validation of differential expression pattern of those was performed using TaqMan assays in these cell populations obtained from a larger cohort of patients and controls. RESULTS: According to the screening assays, three miRNAs were differentially expressed (p value <0.1) in cell populations from both patients and controls: hsa-miR-143, hsa-miR-224 and hsa-miR-576-5p for CD4+ cells, and hsa-miR-10a, hsa-miR-31 and hsa-miR-345 for CD19+ cells. After validation, significant differences (p value <0.05) were confirmed only for hsa-miR-143 and hsa-miR-224 in CD4+ cells and for hsa-miR-10a and hsa-miR-345 in CD19+ cells. In all cases, the miRNAs were over expressed in SLE patients compared with healthy donors. CONCLUSIONS: Our results support a different pattern of miRNA expression in SLE patients.

Association of Toll-like receptor 10 and susceptibility to Crohn's disease independent of NOD2.

Impaired innate inflammatory response has a key role in the Crohn's disease (CD) pathogenesis. The aim of this study was to investigate the possible role of the TLR10-TLR1-TLR6 gene cluster in CD susceptibility. A total of 508 CD patients (284, cohort 1 and 224, cohort 2) and 576 controls were included. TLR10-TLR1-TLR6 cluster single-nucleotide polymorphisms genotyping, NOD2 mutations and TLR10 mRNA quantification were performed using TaqMan assays. Nucleotide-binding oligomerization domain containing 2 (NOD2) and Toll-like receptor (TLR) loci interaction was analyzed by logistic regression and multifactor-dimensionality reduction (MDR). Entropy-based analysis was used to interpret combination effects. One TLR10 haplotype (TLR10(GGGG)) was found associated with CD susceptibility in both cohorts, individuals with two copies had approximately twofold more risk of CD susceptibility than individuals having no copies (odds ratio=1.89, P-value=0.0002). No differences in the mRNA levels were observed among the genotypes. The strongest model for predicting CD risk according to the MDR analysis was a two-locus model including NOD2 mutations and TLR10(GGGG) haplotype (P(c)<0.0001). The interaction gain attributed to the combination of both genes was negative (IG=-2.36%), indicating redundancy or independent effects. Our results support association of the TLR10 gene with CD susceptibility. The effect of TLR10 would be independent of NOD2, suggesting different signaling pathways for both genes.

The STAT4 gene influences the genetic predisposition to systemic sclerosis phenotype.

The aim of this study was to investigate the possible role of STAT4 gene in the genetic predisposition to systemic sclerosis (SSc) susceptibility or clinical phenotype. A total of 1317 SSc patients [896 with limited cutaneous SSc (lcSSc) and 421 with diffuse cutaneous SSc (dcSSc)] and 3113 healthy controls, from an initial case-control set of Spanish Caucasian ancestry and five independent cohorts of European ancestry (The Netherlands, Germany, Sweden, Italy and USA), were included in the study. The rs7574865 polymorphism was selected as STAT4 genetic marker. We observed that the rs7574865 T allele was significantly associated with susceptibility to lcSSc in the Spanish population [P = 1.9 x 10(-5) odds ratio (OR) 1.61 95% confidence intervals (CI) 1.29-1.99], but not with dcSSc (P = 0.41 OR 0.84 95% CI 0.59-1.21). Additionally, a dosage effect was observed showing individuals with rs7574865 TT genotype higher risk for lcSSc (OR 3.34, P = 1.02 x 10(-7) 95% CI 2.11-5.31). The association of the rs7574865 T allele with lcSSc was confirmed in all the replication cohorts with different effect sizes (OR ranging between 1.15 and 1.86), as well as the lack of association of STAT4 with dcSSc. A meta-analysis to test the overall effect of the rs7574865 polymorphism showed a strong risk effect of the T allele for lcSSc susceptibility (pooled OR 1.54 95% CI 1.36-1.74; P < 0.0001). Our data show a strong and reproducible association of the STAT4 gene with the genetic predisposition to lcSSc suggesting that this gene seems to be one of the genetic markers influencing SSc phenotype.

Donor-specific antibody detection: comparison of single antigen assay and Luminex crossmatches.

Luminex bead-based assays are routinely used in the study of anti-human leukocyte antigen (HLA) donor-specific antibodies (DSA). Single antigen (SA) assays use beads coated with recombinant antigens whereas Luminex crossmatch (Xm-DSA) tests consist of beads coated with isolated donor-specific HLA molecules. The aim of this study was to compare these techniques used to detect DSA. A total of 24 sera recognizing different HLA class I (seven anti-HLA-A and seven anti-HLA-B) as well as class II (seven anti-HLA-DR and three anti-HLA DQ) specificities by complement dependent cytotoxicity were included in the study. These sera were used undiluted and in serial dilutions to perform both class I and II SA and Xm-DSA assays. In the case of Xm-DSA the same serum was checked with different lysates. A total of 42 lysates were used to perform a total of 61 crossmatches: 42 to detect anti-class I and 19 to detect anti-class II antibodies. The maximum positive dilution was higher for SA in 76% of the class I and in 90% of the class II crossmatches. Those cases with a higher sensitivity of the Xm-DSA could not be explained by a larger number of antigen targets.

STAT4 associates with systemic lupus erythematosus through two independent effects that correlate with gene expression and act additively with IRF5 to increase risk.

OBJECTIVES: To confirm and define the genetic association of STAT4 and systemic lupus erythematosus (SLE), 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 five new sets of cases and controls for replication. STAT4 cDNA was analysed 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. Transcription of alternative tissue-specific exons 1, indicating the presence of tissue-specific promoters of potential importance in the expression of STAT4, was also detected. 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. The results also indicate that the genes STAT4 and IRF5 act additively to increase the risk for SLE.

A large multicentre analysis of CTGF -945 promoter polymorphism does not confirm association with systemic sclerosis susceptibility or phenotype.

OBJECTIVE: To conduct a replication study to investigate whether the -945 CTGF genetic variant is associated with systemic sclerosis (SSc) susceptibility or specific SSc phenotype. METHODS: The study population comprised 1180 patients with SSc and 1784 healthy controls from seven independent case-control sets of European ancestry (Spanish, French, Dutch, German, British, Swedish and North American). The -945 CTGF genetic variant was genotyped using a Taqman 5' allelic discrimination assay. RESULTS: An independent association study showed in all the case-control cohorts no association of the CTGF -945 polymorphism with SSc susceptibility. These findings were confirmed by a meta-analysis giving a pooled OR = 1.12 (95% CI 0.99 to 1.25), p = 0.06. Investigation of the possible contribution of the -945 CTGF genetic variant to SSc phenotype showed that stratification according to SSc subtypes (limited or diffuse), selective autoantibodies (anti-topoisomerase I or anticentromere) or pulmonary involvement reached no statistically significant skewing. CONCLUSION: The results do not confirm previous findings and suggest that the CTGF -945 promoter polymorphism does not play a major role in SSc susceptibility or clinical phenotype.

Investigation of TLR5 and TLR7 as candidate genes for susceptibility to systemic lupus erythematosus.

OBJECTIVES: The aim of this study was to evaluate the relevance of genetic variants of TLR5 (rs5744168) and TLR7 (rs179008) gene in systemic lupus erythematosus (SLE) in a Spanish population. MATERIAL AND METHODS: Our study population consisted of 752 SLE patients and 1107 healthy controls. All individual were of Spanish Caucasian origin. The TLR5 and TLR7 polymorphisms were genotyped using a PCR system with pre-developed TaqMan allelic discrimination assay. RESULTS: No statistically significant differences were observed when the allele and genotype distribution of TLR5 rs5744168 and TLR7 rs179008 polymorphisms was compared between SLE patients and healthy controls. A significant increase frequency in the CC genotype of the TLR5 rs5744168 polymorphism among SLE patients without nephritis was found (93% vs. 87% in SLE patients with nephritis, p=0.03, OR=2.11 95%CI 0.93-3.51). However, this difference did not reach statistical significance in the allele frequencies (p=0.08). CONCLUSION: These results suggest that the tested variations of TLR5 and TLR7 genes do not confer a relevant role in the susceptibility or severity to SLE in the Spanish population.

Interactive effects of immunoglobulin gamma and human leucocyte antigen genotypes on clearance and persistence of infection with hepatitis C virus.

Particular alleles of human leucocyte antigen (HLA) and immunoglobulin gamma (GM) and immunoglobulin kappa (KM) allotypes (polymorphic determinants of IgG heavy chains and kappa-type light chains, respectively) are associated with the outcome of several infections. To examine their role in the outcome of hepatitis C virus (HCV) infection, we genotyped 50 individuals with resolved and 117 with persistent HCV infection. None of the GM, KM or HLA-C genotypes by themselves were associated with the resolution or persistence of HCV infection. However, particular combinations of HLA and GM genotypes were associated significantly with the outcome of HCV infection. Subjects with the HLA C1C1 genotype, in the absence of GM ff, were more than seven times [odds ratio (OR) 7.15] as likely to have persistent infection as the subjects who lacked both these genotypes. The presence of GM ff, in the absence of HLA C1C2, was associated with the resolution of infection (OR 0.27). The absence of GM fz, in the presence of HLA C2C2, was also associated with the resolution of infection (OR 0.27). Compared to the subjects who lacked both these genotypes, subjects with GM fz, in the absence of HLA C1C2, were almost four times as likely to have persistent infection (OR 3.91); similarly, subjects with HLA C1C2, in the absence of GM fz, were almost three times as likely to have persistent infection (OR 2.80). These results show, for the first time, interactive effects of GM and HLA genotypes in the outcome of HCV infection.

CCL2-2518 A/G and CCR2 190 A/G do not influence the outcome of hepatitis C virus infection in the Spanish population.

AIM: To assess whether CCL2 or interactions between this chemokine and its receptor (CCR2) are associated with outcomes of chronic hepatitis C and with responses to antiviral therapy. METHODS: Two hundred and eighty-four patients with chronic hepatitis C and 193 non-infected matched controls were included in this study. Patients were categorized according to their Scheuer score of hepatic fibrosis as F0-F2 (n = 202) or F3-F4 (n = 82) and according to their response to anti-Hepatitis C virus (HCV) therapy as sustained response (SR, n = 101) or non-sustained response (NSR, n = 98). Genotyping of the -2518 (A/G) CCL2 was performed using PCR-RFLP, genotyping of the 190 (A/G) CCR2 using a PCR-ARMS system, and genotyping of the rs3138042 (G/A) CCR2 using Taqman probes. RESULTS: Univariate analyses identified 4 parameters (infection duration time, viral genotype, gender and AST levels) that tended to influence fibrosis and 7 parameters (CCL2G, CCL2ACCR2A, viremia levels, fibrosis stage, viral genotype, infection duration time and AST levels) that significantly influenced or tended to influence response to treatment. Multivariate analysis identified gender and AST levels as parameters that independently influenced fibrosis stage and viral genotype and infection duration time were the two parameters that independently influenced response to treatment. CONCLUSION: Our results indicate that the mutations studied in the gene pair CCL2/CCR2 do not play a major role in the outcome and response to treatment for HCV infection in the Spanish population.

Lack of association of recipient MCP-1 gene promoter polymorphism with acute graft rejection after orthotopic liver transplantation.

Acute graft rejection after orthotopic liver transplantation (OLT) is associated with leukocyte infiltration of the graft. Monocyte chemoattractant protein-1 (MCP-1) is a beta-chemokine involved in the attraction and accumulation of mononuclear granulocytes toward sites of inflammation. A biallelic polymorphism (G/A) at position -2518 of the MCP-1 gene has been described. Cells obtained from individuals with the GG or AG genotypes have been found to produce more MCP-1 than those obtained from individuals with the AA genotype. The goal of this study was to assess the possible association between this polymorphism and susceptibility to acute graft rejection after OLT. One hundred fifty Caucasian liver transplant recipients from the South of Spain underwent genotyping using a polymerase chain reaction (PCR) amplification followed by restriction fragment length polymorphism (RFLP). No significant differences were observed when patients with versus without acute rejection episodes were compared for the distribution of -2518 MCP-1 genotypes. The present study supports the lack of involvement of polymorphism at position -2518 (A/G) of the MCP-1 gene on the susceptibility to acute allograft rejection among OLT recipients.

IFNL4 ss469415590 polymorphism is associated with unfavourable clinical and immunological status in HIV-infected individuals.

The IFNL4 ss469415590 polymorphism, in high linkage disequilibrium with the IL28B rs12979860 variant, has been associated with hepatitis C virus clearance. We evaluated whether ss469415590 is associated with clinical and immunovirological parameters in human immunodeficiency virus-infected subjects. We found an independent association of the IFNL4 ss469415590 polymorphism with higher prevalence of AIDS-defining illnesses and lower CD4 T cell numbers. These results suggest the existence of common host defence mechanisms against different viral infections.

Association of the CTLA4 3' untranslated region polymorphism with the susceptibility to rheumatoid arthritis.

Cytotoxic T-lymphocyte antigen 4 (CTLA4) gene polymorphism located in the 3' untranslated region (UTR) was investigated in 141 Spanish patients (38 men and 103 women) with rheumatoid arthritis (RA) and in 194 ethnically-matched healthy controls. Twenty alleles having different numbers of (AT) repeats (from 7 to 32) were found in this population. (AT)7 and (AT)16 were the most frequent alleles, and accounted for almost two-thirds of the allelic frequency in the control population. Consequently, alleles were assigned as L (large: 16 or more AT repeats) or S (short: less than 16 AT repeats). When the L/S distribution in patients and controls were compared, an increase of L alleles was observed among patients (49.9% vs. 39.7%; p = 0.02; p(c) = 0.04, odds ratio [OR] = 1.46; 95% confidence interval [CI], 1.06-2.01). Hence, the frequency of S alleles was decreased among patients (51.1% vs. 60.3%; p = 0.02; p(c) = 0.04; OR = 0.69; 95%CI, 0.50-0.95). Moreover, a statistically significant decrease in the frequency of S/S individuals was observed among RA patients (27.7% versus 40.7%; p = 0.01; p(c) = 0.03; OR = 0.56; 95%CI, 0.34-0.91). These differences were irrespective of the HLA "shared epitope" (SE) status, and were observed similarly among SE+ as well as among SE- patients. After combining these data with other reported previously by us, from studies of CTLA4 49 (A/G) and -318 (C/T) polymorphisms, we conclude that the strongest association between CTLA4 gene polymorphisms and RA susceptibility occurs with the 3' UTR polymorphism.

Autoantibodies to transcriptional regulation proteins DEK and ALY in a patient with systemic lupus erythematosus.

A human cDNA expression library that was used to investigate the nature of autoantigens recognized by the serum from a patient with systemic lupus erythematosus revealed the presence of antibodies directed against two transcriptional regulation protein: DEK, a site-specific 45 kD DNA binding protein, likely involved in signal transduction and transcriptional regulation, and a novel 28 kD protein that showed a 94% homology with murine ALY, a nuclear protein that plays a role in regulating the activity of TCRalpha enhancer complex. Whereas autoantibodies directed to epitopes on DEK are commonly found in patients with pauciarticular onset juvenile rheumatoid arthritis, autoantibodies against ALY have not been described and their occurrence has led to the cloning of the cDNA sequence of the first member of the human ALY family.

Association of HLA shared epitope with joint damage progression in rheumatoid arthritis.

A nine years prospective study was performed on 82 Spanish rheumatoid arthritis patients with a disease duration of less than two years at the study entry, in order to evaluate the role of HLA markers in the susceptibility and progression of rheumatoid arthritis. Radiological evaluation of disease severity was performed at the time of diagnosis and 9 years later. High resolution HLA-DR typing demonstrated that the presence of the shared epitope (SE) was more frequent among patients (61% vs. 31% in controls; p = 0.00003; OR = 3.48). Fourteen patients carried two SE+ HLA-DRB1 alleles (SE+/+); 36, one single allele (SE+/-) and 32 were SE negative (SE-/-). HLA-DR4 (particularly DRB1*0401 and DRB 1*0405) and HLA-DR10 were increased among patients. At study entry, the frequencies of locally severe (hands and feet) RA were more frequent among SE+/+ patients (79%) than among SE+/- (47%) and SE-/-(44%) patients (p = 0.05; RR = 1.80). After 9 years of disease these differences disappeared, whereas differences in the extent of the disease arise: 79%, 50% and 32% of SE+/+, SE+/- and SE-/- patients respectively showed large joints involvement (shoulders, elbows, hips and knees) (p = 0.01; RR = 2.44 for SE+/+ vs. SE-/-; and p = 0.04; RR = 1.81 for SE+ vs. SE-). These results suggest that the presence of the shared epitope is associated with the extent and progression of radiological joint damage in rheumatoid arthritis.

Complex associations between HLA-DRB1 genes and female rheumatoid arthritis: results from a prospective study.

We followed 138 Spanish patients (37 men and 101 women) with rheumatoid arthritis (RA) to analyze whether patient sex influenced the HLA-DRB1 associations with disease susceptibility. Results showed that, although a high increase of the shared epitope (SE) was observed in both genders, distribution of HLA-DRB1 specificities differs from males to females: DR1 was increased among male patients, whereas DR4 as well as DR10 were preferentially associated with female RA. To further explore whether this phenomenon operates either on susceptibility or on disease progression, 82 patients (25 males and 57 females) among the whole group were followed during the first 8 to 10 years of their disease. Results from this prospective study showed that the association of the SE with radiological disease severity was found in both male and female patients, although it was stronger among the latter group. Interestingly, DR1- as well as DR4-related alleles contributed to the high frequency of SE among female patients with early small-joints severe RA and/or long-term large-joint erosions. These results suggest that HLA polymorphism might be involved in RA pathogenesis through two mechanisms: (a) in combination with patient sex, operating in disease induction; and (b) independent of patient sex, influencing disease severity and progression.

Hereditary spherocytosis associated with mutations in HFE gene.

We report on a Spanish family in which three members of different generations were diagnosed with hereditary spherocytosis (HS). Additionally, one of them II-I (44-years-old), presented iron overload with hepatic deposit and needed treatment with periodic phlebotomies. The rest of the family members presented normal analytical values in iron metabolism. To investigate the presence of H63D and C282Y mutations in the HFE gene, patient II-I was found to be compound heterozygous and was the only family member presenting HS and this genetic condition in HFE. We propose a synergistic effect of HS and mutations in HFE as the cause of the iron deposits.

[Serologic and molecular HLA typing in patients from Andalucia with Behçet's disease. Genetic and clinical correlations]. / Tipificación HLA serológica y molecular en pacientes andaluces con enfermedad de Behçet. Correlaciones geneticoclínicas.

BACKGROUND: HLA typing was performed in 67 patients with Behçet's disease from Andalucia, Spain to: 1) analyze the association of class I and II molecules with Behçet's disease in Spain; 2) study the clinical correlations and 3) evaluate its diagnostic and/or prognostic role. PATIENTS AND METHODS: 1) Serologic typing (microlymphocytotoxicity): class I molecules in 67 patients and class II molecules in 47 patients (controls: 223 healthy volunteers). 2) Oligotyping (PCR-SSO): class II molecules (DQB1 and generic DRB1) in 47 patients and 189 controls. 3) STATISTICAL ANALYSIS: chi square test (dicotomic variables) and Student t test (continuous variables), and calculation of the relative risk by the Wolff and Haldane formulas. RESULTS: The HLA B51 antigen was the most frequently observed in the whole series (p = 0.003) in males with ocular disease (p = 0.0001) and in patients with cutaneous (p = 0.001) and digestive involvement (p = 0.05). The HLA B51-positive males were younger at disease onset (p = 0.01) with neurologic involvement being infrequent (p = 0.03). The HLA B51 antigen was associated with neurologic (p = 0.06) and articular involvement (p = 0.05). The DQB1*0303 was associated with uveitis of bad evolution (p = 0.01). The DR11 and DQB1*0301 were more frequent in HLA B51-positive patients and the DQ5 was negatively associated with Behçet's disease, particularly in the HLA B51-positive patients. CONCLUSIONS: The study of the HLA antigens provides useful information for the diagnosis of Behçet's disease, aids in differentiating the different clinical forms and has prognostic significance.

[Study of the gene of hemochromatosis in first degree relatives of patient with porphyria cutanea tarda]. / Estudio del gen de la hemocromatosis en familiares en primer grado de una paciente con porfiria cutánea tarda.

BACKGROUND: Porphyria cutanea tarda (PCT) is characterized by a deficiency of uroprophyrinogen decarboxylase (URO-D). The activity of this enzyme is decreased in the presence of iron-dependent disorders. A relationship between the hepatic hemosiderosis, which is present in most patients with PCT, and the status of the hemochromatosis gene has been observed. Particularly, two mutations of the gene have been described, one of them (Cys282Tyr) is related to the iron overload and might influence on the development of the clinical signs of PCT. PATIENTS AND METHODS: We have measured the transferrin saturation percentage and observed the status of the hemochromatosis gene in a patient diagnosed with PCT and in five of their relatives. RESULTS: The proband and one sister had a marked increase of uroporphyrins and iron overload, and both had the mutation Cys282Tyr, which was also present in the mother. CONCLUSIONS: This is the first study measuring iron overload and hemochromatosis gene mutations in relatives, and not in patients with PCT. We think that the study of this family justifies the systematic investigation of these parameters in all first degree relatives of patients with PCT, to identify subjects at risk, who can benefit from prophylactic measures and early therapy.