Mucous membrane pemphigoid: HLA-DQB1*0301 is associated with all clinical sites of involvement and may be linked to antibasement membrane IgG production

BACKGROUND: Class I human leucocyte antigens (HLA) -A, -B, -Cw and class II HLA-DRB1, -DQB1 alleles were determined in 131 British Caucasian patients with mucous membrane pemphigoid (MMP) using serological and DNA-based methods. OBJECTIVES: To analyse the class I and II alleles expressed in well-defined clinical and immunopathological subgroups of MMP, in order to establish whether specific alleles or haplotypes might in part explain disease susceptibility, clinical sites of involvement or disease severity. METHODS: Subgroups of patients were analysed according to the following clinical criteria: age of onset, sex, sites of clinical involvement (oral, ocular, skin, nasal, genital, pharyngeal, oesophageal, laryngeal, perianal), disease severity and history of autoimmune disease. Subgroups were also analysed according to the following immunopathological criteria: autoantibody profile, the presence of circulating antibasement membrane IgG or IgA antibodies and the detection of target basement membrane zone (BMZ) antigens (BP230 and BP180) by IgG autoantibodies. RESULTS: Class I HLA typing showed no significant disease or subgroup associations. Class II DRB1 typing showed a significantly increased allelic frequency in MMP vs. controls for DRB1*11 (RR = 2.08, Pc < 0.0000056). For DQB1, MMP vs. controls, there was a significantly increased allelic frequency for DQB1*0301 (Pc < 0.00000028) in both males and females; all clinical sites of involvement, with the exception of laryngeal, oesophageal and perianal sites and in patients with detectable circulating anti-BMZ IgG compared with those negative for IgG (P < 0.0096, Pc < 0.019). A positive trend was noted in patients with ocular involvement compared with no ocular involvement and in patients with a clinical score > or = 10 compared with < 10. We found no difference in DQB1*0301 allele frequency between subgroups with or without BP180 or BP230 target antigens. Haplotype frequencies showed an increase in DRB1*04, DQB1*0301 (Pc < 0.000066) and DRB1*11, DQB1*0301 (Pc < 0.000002) among patients compared with controls. CONCLUSIONS: The DQB1*0301 allele confers a predisposition to all subgroups of MMP and may have a role in T-cell recognition of basement membrane antigens, resulting in the production of anti-BMZ IgG autoantibodies. The positive trend between increased allelic expression of DQB1*0301 in patients with ocular disease and in those with a higher clinical score, further suggests a role for this allele in disease severity.     

广东籍汉人HLA-DQA DQB基因与SLE的易感性研究

目的　探讨SLE患者遗传易感性与HLA DQ基因分型的相关性。方法　以广东籍健康者及SLE患者全血为研究标本 ,DNA的提取用快速盐析法 ,HLA DQ基因分型用序列特异性引物 (SSP)法。结果　SLE患者组中DQA1 0 10 1等位基因的检出率明显高于正常组 (RR =3 .12 ,Pc =0 .0 3 6) ,DQA1 0 3 0 2等位基因的检出率则明显低于正常组(RR =0 .0 9,Pc =0 .0 45 ) ;SLE患者组中DQB1 0 3 0 1的检出率明显低于正常组 ,与正常组比较有显著性差异 (P <0 .0 1)。结论　广东籍汉族SLE与HLA DQ的相关性方面 ,DQA1 0 10 1起主导作用 ;广东籍汉族SLE患者中 ,疾病的保护性基因在本研究中表现为DQA1 0 3 0 2、DQB1 0 3 0 1。     

广西壮族、汉族系统性硬化病与HLA-DQA1、DQB1等位基因相关性研究

目的 探讨广西壮族、汉族系统性硬化病(SSC)与HLA-DQA1、-DQB1等位基因的相关性.方法 用PCR-序列特异性引物(PCR-SSP)方法,对壮、汉族Sse患者各50例和壮、汉族健康人各100例的HLA-DQA1、-DQB1基因进行研究.结果 与正常人对照组相比,壮族SSc患者组中HLA-DQA1*0401、-DQB1*0501、-DQB1*0601基因频率显著升高(分别为RR:4.06,χ2=15.41,Pc<0.01;RR=4.47,χ2=10.65,Pc<0.01和RR=3.47,χ2=10.06,Pc<0.01),汉族SSc患者组中HLA-DQA1*0401、-DQA1*0601、-DQB1*0601基因频率显著升高(分别为RR=9.33,χ2=8.37,Pc<0.05;RR=8.071,χ2=20.13,Pc<0.01和RR=3.76,χ2=10.76,Pc<0.01).壮、汉族SSc患者组中HLA-DQA1*0201基因频率均显著降低(χ2=13.58,Pc<0.01和χ2=12.21,Pc<0.01).结论 HLA-DQA1*0401、-DQB1*0601可能是广西壮族、汉族SSc患者的易感基因,HLA-DQB1*0501可能是广西壮族SSc患者的易感基因,HLA-DQA1*0601可能是广西汉族SSc患者的易感基因.

Abstract：

Objective To explore the potential associations of HLA-DQA1 and DQB1 alleles with systemic scleroderma (SSc) in Zhuang and Han nationalities in Guangxi Zhuang Autonomous Region. Methods Genomic DNA was extracted from the peripheral blood of SSc patients of Zhuang (n=50) and Han (n=50) nationality,normal controls of Zhuang (n=100) and Han (n=100) nationality in Guangxi Zhuang Autonomous Region.PCR with sequence-specific primers (PCR-SSP) was used to detect HLA-DQA1 and -DQB1 alleles in these subjects. Results There was a significant increase in the frequency of HLA-DQA1*0401, -DQBl*0501 and -DQB1*0601 alleles in the patients of Zhuang nationalty(RR=4.056,χ2=15.407,PC=0.001;RR=4.472,χ2=10.653,Pc=0.004;RR=3.473,χ2=10.06,Pc=0.008)compared with normal controls of Zhuang nationality,and in the frequency of HLA-DQA1*0401,DQA1*0601 and DQB1*0601 alhles in patients of Han nationality (RR=9.333,χ2=8.371,Pc=0.036;RR=8.071,χ2=20.130,Pc=0.000;RR=3.764,χ2=10.755,Pc=0.004)compared with normal control of Han nationality.However,the frequency of HLA-DQA1*0201 allele was statistically lower in the patients of Zhuang and Han nationality than in the controls of corresponding nafionality (χ2=13.583,Pc=0.002;χ2=12.209,Pc=0.004).Conclusions HLA-DQA1*0401 and-DQB1*0601may be susceptible genes for SSc in Zhuang and Han nationalities,HLA-DQB1*0501 for Sse in Zhuang nationality,and HLA-DQAl*060l for SSc in Han nationality in Guangxi Zhuang Autonomous Region.     

Polymorphisms of HLA-DR and -DQ genes in Japanese patients with bullous pemphigoid

Bullous pemphigoid (BP), an autoimmune skin disease of the elderly, is mediated by autoantibodies that bind to hemidesmosomes of epidermal basal cells. This study investigated BP-associated HLA-DR and -DQ genes among Japanese patients. We analyzed HLA-DR and -DQ genes among 23 Japanese BP patients based on the polymerase chain reaction-restriction fragment length polymorphism. Eighteen of these 23 patients (78%) carried at least one allele of HLA-DRB1*04 or DRB1*1101, with significant increases in HLA-DRB1*04 (*0403, *0406)/DQA1*0301/DQB1*0302 and DRB1*1101/DQA1*0505/DQB1*0302 haplotypes as well as the individual alleles DRB1*1101 and DQB1*0302 (corrected p < 0.05 for each comparison), when compared to control subjects. These data differ from the accepted DQB1*0301 (DQ7) association with the same disease among Caucasians. These findings indicate that different HLA class II haplotypes genetically influence susceptibility to BP among different ethnic groups. Our findings, together with previous reports on Caucasian patients with the pemphigoid group of bullous diseases, suggest that HLA-DRB1 molecules might participate in the regulation of autoimmune responses to BP antigens.     

HLA DQB1*0301 allele is involved in the susceptibility to erythema multiforme

Erythema multiforme (EM) is an acute, episodic inflammatory disorder of the skin and mucous membranes of various etiology that could be related to immunologic hypersensitivity response. EM has been previously reported to be associated with serologically defined HLA-DRw53 and DQw3 antigens. In this report, we reevaluate the role of HLA class II alleles in EM manifestations. With use of the polymerase chain reaction, followed by sequence-specific oligonucleotide hybridization, 35 unrelated Caucasian EM patients and 80 randomly selected healthy subjects were studied, and the DRB3, DRB4, DQA1, and DQB1 alleles were analyzed. The comparison of frequencies of these alleles indicates that (i) susceptibility to EM disease is more associated with the HLA-DQ than the HLA-DR subregions and (ii) that the DQB1*0301 is the most frequent allele among EM patients. Sixty-six percent of the patients had the DQB1*0301 allele compared to 31% of the controls (RR = 4.1; p less than 0.001). An even stronger DQB1*0301 association was found in the patient group with herpes-associated EM (76%; RR = 6.5; p less than 0.001). Our data demonstrate a clear association between an HLA-DQB1 allele and susceptibility to EM.     

HLA-DR and DQ polymorphisms in bullous pemphigoid from northern China

Bullous pemphigoid (BP) is an autoimmune disease mediated by autoantibodies against hemidesmosome components. This study used PCR-sequence-specific primers to genotype polymorphisms in HLA-DR and DQ in 25 BP patients and 57 normal controls from northern China. We found lower frequencies of DRB1*08 (DR8) and DRB1*08/DQB1*06 (DR8/DQ6) haplotypes in BP patients than in controls (4.08% vs. 15.19% and 1.54% vs. 13.82%, respectively; P < 0.05), suggesting a protective role for DR8 and DR8/DQ6 haplotypes in BP patients from northern China; there were no statistical differences among other alleles tested. This result is strikingly different from previous reports that DQB1*0301 is associated with BP in Caucasian patients and DRB1*1101, DQB1*0302, DRB1*04/DQA1*0301/DQB1*0302 and DRB1*1101/ DQA1*0505/DQB1*0302 with Japanese BP patients. Ethnic differences in the polymorphic composition of the HLA-DR and DQ genes may influence genetic susceptibility to BP.     

Antigen specificity in subsets of mucous membrane pemphigoid

Mucous membrane pemphigoid (MMP) has several subsets based on target antigens recognized by their sera. MMP and ocular cicatricial pemphigoid (OCP) sera recognize beta4 integrin subunit, oral pemphigoid sera recognize alpha6 integrin subunit, and anti-epiligrin cicatricial pemphigoid sera recognize laminin 5. Our aim is to determine if autoantibodies in the sera of patients with MMP, OCP, and oral pemphigoid (OP) recognize only their target antigens, and to see if this specificity is maintained throughout the clinical course. An immunoblot assay using bovine gingival lysate was used as substrate. Fifteen MMP patients, eight with OCP, and 15 OP patients were studied before therapy and at multiple intervals during the clinical course. Absorption and blocking studies were performed to determine binding specificity. Sera of patients with MMP and OCP recognize only beta4 integrin subunit, and sera of OP patients recognize alpha6 integrin throughout the clinical course. The sera of patients in the subsets of MMP described in this report show adherence and selectivity to target antigen during the entire clinical course, without crossover, interaction, or change. Hence, these subsets of MMP provide an excellent model to study clinical correlation with antigen and antibody specificity, in autoimmunity.     

壮族人寻常性银屑病与HLA-DQA1和DQB1基因的相关性研究

[摘要]目的：探讨广西壮族人寻常型银屑病的发病与HLA-DQA1和DQB1基因的关联。方法：应用聚合酶链式反应-序列特异引物（PCR-SSP）法对58例壮族寻常型银屑病患者和102例健康壮族人的HLA-DQA1和DQB1座位进行基因分型，比较两组相应等位基因的频率。结果：HLA-DQB1*0303与壮族银屑病患者呈显著的正相关（OR=4.540，p=0.004），而HLA-DQA1*0501和HLA-DQB1*0301与壮族银屑病患者呈显著的负相关（OR=0.189，p=0.000；OR=0.367，p=0.018）。结论：以上3个HLA-DQ等位基因与广西壮族人寻常型银屑病的关系密切，其中HLA-DQB1*0303可能为该人群银屑病的易感因子，而HLA-DQA1*0501和HLA-DQB1*0301则可能对银屑病有抵抗作用。     

Bullous pemphigoid antigen II (BP180) and its soluble extracellular domains are major autoantigens in mucous membrane pemphigoid: the pathogenic relevance to HLA class II alleles and disease severity

BACKGROUND: Mucous membrane pemphigoid (MMP), a chronic autoimmune subepithelial blistering disease, is associated with circulating IgG and/or IgA autoantibodies against several basement membrane zone antigens. The heterogeneity of clinical presentation and diversity of target autoantigens have contributed to difficulties in characterizing this condition immunologically. OBJECTIVES: To analyse serum autoantibody profile and HLA class II alleles in MMP patients and to correlate this with the clinical presentation of disease. METHODS: Well-defined subgroups consisting of 124 patients with MMP were examined for IgG and IgA reactivity with immunoblotting using human epidermal, dermal and placental amnion proteins. The results were further analysed on the basis of detailed clinical (sites of involvement and disease severity) and immunopathological criteria (immunofluorescence study and HLA class II alleles). RESULTS: Immunoblot assay revealed that the majority of MMP patients had IgG (93 of 124, 75%) and/or IgA autoantibodies (63 of 124, 51%) to BP180 (including its soluble ectodomains, 120-kDa LAD-1 and 97-kDa LABD97 antigens). Other antigens targeted predominantly by IgG autoantibodies included: BP230 in 34 (27%), beta4 integrin in 26 (21%), and laminin 5 in three (2%). All the BP230+ sera and 23 (88%) beta4 integrin+ sera also reacted with at least one of the BP180 antigens. Over 85% of patients with reactivity to beta4 integrin had ocular involvement. In most cases of MMP, more severe clinical features were associated with antibody reactivity to multiple basement membrane zone antigens, as well as reactivity to multiple BP180 component antigens. Dual BP180/LAD-1 reactivity with IgG and IgA was associated with a more severe phenotype. In addition, the subset-dependent autoantibody reactivity correlated well with specific HLA class II alleles, DQB1*0301, DRB1*04 and DRB1*11. CONCLUSIONS: Our results confirmed that BP180 is a major autoantigen targeted by the sera of patients with MMP. The disease-prevalent HLA class II alleles and humoral autoimmune response against the particular subsets of antigenic epitope(s) within BP180 ectodomain may contribute to the clinicopathological significance and disease severity of MMP.     

A child with localized vulval pemphigoid and IgG autoantibodies targeting the C-terminus of collagen XVII/BP180

Localized vulval pemphigoid of childhood (LVPC) has previously been reported in six girls. Clinical features and immunopathological data have suggested it to be a morphological variant of bullous pemphigoid. Epitope targets of the autoantibodies of these patients have not been defined in detail. We describe a 9-year-old girl with possible cicatricial LVPC and circulating IgG antibodies directed against native collagen XVII/BP180, its 120-kDa soluble ectodomain and against the C-terminus of collagen XVII/BP180. No reactivity was detected towards the NC16A domain of collagen XVII/BP180. Linear IgG and C3 deposits were found along the cutaneous basement membrane zone. On 1 mol/L salt-split skin, IgG autoantibodies were shown to bind to the epidermis, and the HLA type II allele DQB1*0301, a marker with significantly increased occurrence in patients with ocular and oral cicatricial pemphigoid, was identified in this patient. Our data suggest that LVPC is a variant of bullous pemphigoid in which direct immunofluorescence microscopy combined with immunoblot analysis can deliver valuable diagnostic information for differential diagnosis. However, differentiation between the scarring and non-scarring course of the disease cannot be made with the present diagnostic markers and therefore careful follow-up of patients with LVPC is required.     

Human leukocyte antigen class II alleles and natural history of HPV 2/27/57-induced common warts

Epidemiological studies have demonstrated an association between HLA-DQB1*03 alleles and the risk of cervical cancer induced by human papillomavirus (HPV). As persistence of HPV infection is required for developing cervical cancer, we wanted to elucidate the role of HLA-class II allele polymorphisms in the persistence of common warts induced by HPV 2, HPV 27 or HPV 57. Therefore, we determined the distribution of HLA-DQA1, -DQB1, and -DRB1 alleles in 71 patients presenting with HPV 2/27/57-induced common warts which had persisted for at least 18 months as well as in 92 individuals who had never suffered from common warts or whose warts had healed in less than 18 months. Among patients with long-lasting warts, the carriership frequencies and allele frequencies of DQA1*0301, DQB1*0301, DRB1*07 and DRB1*09 were higher, and the allele frequencies of DQA1*0501, DQB1*0603, DRB1*01 and DRB1*03 were lower. Statistically significant differences (Bonferroni adjusted Fishers exact test) were found for carriership frequency of DQA1*0301 (46.5 vs 21.7%, P=0.013) and for carriership frequency (18.3 vs 1.1%, P=0.0015) and allele frequency (12 vs 0.5%, P=0.000013) of DQB1*0301. A greater proportion of patients with long-lasting warts than of subjects without persistent warts were homozygous at the DQA1 (14.1 vs 6.5%) and DQB1 (16.9 vs 8.6%) gene loci. These results suggest that the natural history of cutaneous HPV 2/27/57-induced common warts may be modulated by allele polymorphisms at the HLA-DQA1 and HLA-DQB1 gene loci.     

The association between HLA DR, DQ antigens, and vulval lichen sclerosus in the UK: HLA DRB112 and its associated DRB112/DQB10301/04/09/010 haplotype confers susceptibility to vulval lichen sclerosus, and HLA DRB10301/04 and its associated DRB10301/04/DQB10201/02/03 haplotype protects from vulval lichen sclerosus

Lichen sclerosus (LS) is considered to have an immunogenetic background. Several small studies, using serological typing, have reported that HLA-DR11, DR12, and DQ7 were increased in LS, with DR17 less frequent. This study aimed to validate and detect new HLA-DR and DQ associations with LS in females and its characteristic clinical parameters. The cases, 187 female LS patients, and 354 healthy controls were all UK North Europeans. PCR-sequence specific primers method was applied to genotype the HLA-DR, DQ polymorphisms that correspond to 17 serologically defined DR and seven DQ antigens. Statistical analysis was performed with two-tailed Fisher's exact test with Bonferroni adjustment (p value after Bonferrroni adjustment, Pc). We found increased frequency of DRB1*12 (DR12) (11.2%vs 2.5%, pc < 0.01) and the haplotype DRB1*12/DQB1*0301/04/09/010 (11.2%vs 2.5%, p < 0.001, pc < 0.05), and a lower frequency of DRB1*0301/04 (DR17) (11.8%vs 25.8%, pc < 0.01) and the haplotype DRB1*03/DQB1*02DRB1*0301/DQB1*0201/02/03 (11.2%vs 24.6%, pc < 0.0001) in patients compared with controls. HLA DR and DQ antigens were not associated with time of onset of disease, site of involvement, structural changes of genitals, and response to treatment with potent topical steroids. In conclusion, HLA-DR and DQ antigens or their haplotypes appear to be involved in both susceptibility to and protection from LS.     

HLA-DQA1 and DQB1 alleles are associated with genetic susceptibility to psoriasis vulgaris in Chinese Han

BACKGROUND: Psoriasis vulgaris is a chronic skin disorder characterized by infiltration of inflammatory elements, keratinocyte hyperproliferation and altered differentiation. Although the pathogenesis of psoriasis is not fully understood, there is solid evidence of a susceptibility locus in the human leukocyte antigen (HLA) region. OBJECTIVES: To investigate whether HLA-DQA1 and DQB1 alleles are associated with genetic susceptibility to psoriasis vulgaris in Chinese Han. PATIENTS AND METHODS: The polymerase chain reaction-sequence-specific primer (PCR-SSP) method was used to analyse the distribution of HLA-DQA1 and DQB1 alleles in 189 patients with psoriasis and 273 healthy controls. RESULTS: The HLA-DQA1*0104 (OR = 2.33, P = 0.0001154, Pc = 2.0 x 10-3), DQA1*0201 (OR = 3.36, P < 1.0 x 10-7, Pc < 1.0 x 10-6), DQB1*0201 (OR = 1.64, P = 0.0192, Pc > 0.05) and DQB1*0303 (OR = 1.55, P = 0.0377, Pc > 0.05) alleles were more prevalent in patients with psoriasis vulgaris than in controls, and HLA-DQA1*0501 (OR = 0.30, P = 0.0000039, Pc < 4.0 x 10-5) alleles were less prevalent. The HLA-DQA1*0104 (OR = 2.42, P = 0.0001159, Pc < 2.0 x 10-3), DQA1*0201 (OR = 3.74, P < 1.0 x 10-7, Pc < 1.0 x 10-6) and DQA1*0501 (OR = 0.30, P = 0.0000374, Pc < 4.0 x 10-4) alleles were only associated with type I psoriasis. HLA-DQA1*0104 and DQA1*0201 were more prevalent in patients with or without a family history of psoriasis. However, the DQA1*0501 allele was only more prevalent in patients without a family history of psoriasis. CONCLUSION: HLA-DQA1*0104 and DQA1*0201 alleles may be psoriasis susceptibility genes or may be in close linkage with the susceptibility genes. The HLA-DQA1*0501 allele seems to have a protective effect against the development of psoriasis vulgaris in Chinese Han. There may be a difference in genetic background between psoriasis patients with and without a family history of psoriasis.     

Mycosis fungoides: HLA class II associations among Ashkenazi and non-Ashkenazi Jewish patients

BACKGROUND: An immunogenetic mechanism has been suggested to play a role in the pathogenesis of mycosis fungoides (MF). While results of studies on HLA class I associations haveproved inconsistent, two previous studies showed that certain HLA class II alleles were significantly increased among North American caucasian patients with MF: HLA-DRB1*11 and DQB1*03. OBJECTIVES: To investigate the possible HLA class I and class II associations with MF among Jewish patients. METHODS: The patient group comprised 68 Jewish patients with MF: 38 Ashkenazi and 30 non-Ashkenazi. The control group comprised 252 healthy Jewish volunteers: 132 Ashkenazi and 120 non-Ashkenazi. Tissue typing for HLA class I (A and B) was performed using the National Institutes of Health microlymphocytotoxicity technique. DNA-based low-medium resolution analysis for DRB1* and DQB1* alleles was performed using polymerase chain reaction (PCR) amplification with sequence-specific primers. For those alleles found to have significantly increased frequency, high-resolution analysis was done by means of PCR sequence-specific oligotyping. RESULTS: The allele frequency of HLA-DRB1*11 was found to be significantly increased but only among Ashkenazi patients with MF (30% vs. 19% in the controls; P = 0.034). High-resolution analysis for DRB1*11, not previously performed, suggested that its greater frequency is due to the increased number of Ashkenazi MF patients with the DRB1*1104 allele (P corrected = 0.036). Analysed together, DQB1*03 alleles (DQB1*0301-0304) had a significantly greater frequency in MF as a group as compared with controls (47% vs. 33%, P = 0.003). DQB1*0301 was demonstrated to be the specific allele associated with MF in Jewish patients (allele frequency of 36% vs. 23% in controls; P corrected = 0.0068), which was not the case for North American caucasian patients with MF. No greater frequencies of any of the HLA class I A or B antigens were found. CONCLUSIONS: Our findings further demonstrate the 'universality' of MF HLA class II susceptibility alleles, i.e. HLA-DRB1*11 and HLA-DQB1*03, suggesting that HLA polymorphism is likely to be important in the pathogenesis of MF in Jewish patients, as it is in North American caucasian patients. Not previously reported is our finding that HLA-DRB1*1104 is the specific allele more prevalent among patients with MF. Our study also underscores some differences in HLA profiles between non-Jewish and Jewish patients with MF and between Ashkenazi and non-Ashkenazi Jewish patients, indicating the possibility of diverse HLA disease associations in populations with different genetic backgrounds. Our study provides further evidence for the lack of association between HLA class I and MF.     

HLA class II polymorphisms in Spanish melanoma patients: homozygosity for HLA-DQA1 locus can be a potential melanoma risk factor

BACKGROUND: The association of melanoma with HLA class II loci is under extensive debate. Different investigators have found discrepant results due to, at least in part, sample size, patient series heterogeneity, choice of control population and differences in the techniques employed for the detection of HLA antigens and alleles. OBJECTIVES: This study was designed to analyse the possible association of melanoma with HLA class II loci with regard to different clinic pathological factors and to investigate other risk factors for melanoma susceptibility, such as HLA homozygosity. PATIENTS AND METHODS: HLA-DRB1, -DQA1 and -DQB1 genotyping was performed for 117 eastern Spanish patients presenting with primary melanoma. RESULTS: Although there were no significant alterations in the phenotypic frequencies of HLA-DQA1, -DQB1 or -DRB1 alleles in any subgroup of patients when compared with controls, patients exhibited a statistically significant increase in HLA-DQA1 homozygosity rate. This DQA1 homozygosity-specific association was particularly dependent on some features in melanoma patients such as light hair colour, skin type I or II, early age at diagnosis, absence of atypical naevi, or abscence of atypical naevus syndrome phenotype (aetiological fractions about 10-20%). Analysis of homozygosity for single DQA1 alleles showed an increased homozygosity rate for DQA1*0505 and DQA1*0301 in comparison with controls. These DQA1 alleles are in strong linkage disequilibrium with DQB1*0301 in white populations, and DQB1*0301 homozygous individuals were significantly increased in red in or fair-haired patients (relative risk 5.65). CONCLUSIONS: Our results indicate that the contribution of HLA class II alleles to primary melanoma incidence is not significant in the Spanish population. However, homozygosity for the HLA-DQA1 locus (and, perhaps, for the HLA-DQB1*0301 allele) might be considered a potential risk factor for developing melanoma depending on the person's genetic background and, perhaps, on certain environmental conditions.     

自体血清皮肤试验阳性慢性荨麻疹与HLA-DRB1基因的相关性研究

目的 探讨广西地区自体血清皮肤试验阳性慢性荨麻疹与HLA-DRB1等位基因遗传易感性的关系。 方法 对144例广西地区慢性荨麻疹患者进行自体血清皮肤试验,按试验结果分为阳性组62例,阴性组82例。采用聚合酶链反应-序列特异性引物方法,对患者组和199例正常人对照组进行HLA-DRB1等位基因的分型,并分析DRB1基因在3个组中的分布。使用SPSS13.0统计软件分析。结果DRB1*01、*1401、*16等位基因频率在阳性组、阴性组和正常人对照组间比较,差异均有统计学意义（χ2 = 10.92,Pc = 0.03;χ2 = 35.34,Pc < 0.01;χ2 = 12.69,Pc = 0.03）。进一步在各组间进行两两比较,仅DRB1*1401等位基因频率在自体血清皮肤试验阳性组与对照组间（RR = 17.09,Pc < 0.01）及自体血清皮肤试验阳性组与阴性组间（RR = 7.20,Pc < 0.01）,差异均有统计学意义。结论 DRB1*1401等位基因可能是广西地区自体血清皮肤试验阳性慢性荨麻疹的易感基因或与其连锁。     

Tunisian endemic pemphigus foliaceus is associated with the HLA-DR3 gene: anti-desmoglein 1 antibody-positive healthy subjects bear protective alleles

Background  Pemphigus foliaceus is an autoimmune blistering skin disease that partly results from genetic factors, especially human leucocyte antigen (HLA) class II genes.
Objectives  The aim of the study was to determine the HLA DR/DQ markers of susceptibility and protection in the Tunisian endemic form.
Methods  Genomic DNA from 90 patients with pemphigus foliaceus recruited from all parts of the country and matched by age, sex and geographical origin with 270 healthy individuals, was genotyped.
Results  Firstly, when the whole patient population was studied, DRB1*03 , DQB1*0302 and DRB1*04 alleles were significantly associated with the disease while a significant decrease of, in particular, DRB1*11 and DQB1*0301 was observed in patients compared with controls. DRB1*0301 was the dominant allele in DR3-positive patients and controls, while DRB1*0402 was found in 42% of DR4-positive patients. Secondly, when the HLA DR/DQ allele distribution was studied after dividing patients according to their geographical origin, the southern group, which consisted exclusively of patients with the endemic form of the disease, showed the same associations as the whole pemphigus foliaceus population, particularly with DRB1*03 . In the northern group, only the DRB1*04 and DQB1*0301 alleles were found to be associated. Interestingly, anti-desmoglein 1 antibody-positive healthy controls did not carry susceptibility alleles but, in contrast, most carried negatively associated alleles.
Conclusions  These observations indicate that a particular genetic background characterizes the Tunisian endemic form of pemphigus foliaceus and that HLA class II genes control the pathogenic properties of the autoimmune response rather than the initial breakage of B-cell tolerance.     

广西壮族系统性红斑狼疮与HLA-DQA1基因相关性研究

目的　为了探讨广西壮族系统性红斑狼疮 (SLE)与HLA DQA1相关性。方法　用聚合酶链反应 序列特异性引物 (PCR SSP)技术 ,对 5 1例SLE壮族患者和 70例壮族健康人的HLA DQA1基因进行研究。结果　两组均未发现HLA DQA1 0 2 0 1, 0 3 0 2及壮族健康人的DQA1 0 60 1等位基因。SLE组DQA1 0 10 1频率显著高于对照组 (RR =3 .2 72 7,χ2 =7.3 2 1,P =0 .0 0 9) ,而DQA1 0 10 4, 0 3 0 1频率均显著低于对照组 (RR =0 .45 61,χ2 =3 .885 ,P =0 .0 49和RR =0 .43 17,χ2 =4.843 ,P =0 .0 2 8)。结论　DQA1 0 10 1可能是广西壮族SLE易感基因 ,DQA1 0 10 4和DQA1 0 3 0 1可能为保护基因。     

Human leukocyte antigens class I and class II in patients with pemphigus in southern Turkey

Background Genetic factors that predispose individuals to pemphigus are considered to play important roles in the development of the disease. Furthermore, population studies of patients with pemphigus have clearly shown that the most prevalent alleles differ across ethnic groups. Objectives This controlled study was designed to detect the distribution of human leukocyte antigen (HLA) class I and II alleles in Turkish patients with pemphigus. Methods Sixty patients diagnosed with pemphigus according to clinical findings, histology, immunofluorescence, and enzyme‐linked immunosorbent assay (ELISA) were enrolled in the study. The control group consisted of 60 healthy adult transplant donors. HLA typing was carried out using a polymerase chain reaction (PCR) with sequence‐specific primers (SSP) method. Results The frequencies of HLAs A*11, CW*01, DRB1*04, DRB1*14, DQB1*05, and DPB1*0401 were found to be statistically significantly higher in the disease group than in controls. By contrast, the frequencies of HLAs B*18, B*50, DRB1*11, DQB1*02, DQB1*06, DPB1*0301, and DPB1*1102 were statistically significantly lower in the pemphigus group than in controls. Linkage dysequilibrium analysis showed that DRB1*14/DQB1*05, A*11/DQB1*05, and A*11/DRB1*14 alleles were detected frequently in pemphigus patients, and DRB1*11/DQB1*05, DRB1*14/DQB1*02, B*50/DQB1*02, and B*50/DPB1*0301 alleles appeared frequently in healthy controls. Conclusions The results suggest that DRB1*04, DRB1*14, DQB1*05, and DPB1*0401 class II HLAs and A*11 and CW*01 class I HLAs are associated with pemphigus in southern Turkey. Observed differences in LD patterns between patients and controls suggest that the coexistence of the respective alleles is strongly determinant of predisposition towards (DRB1*14/DQB1*05 and A*11/DQB1*05) or protection against (B*50/DQB1*02) the disease.     

Association of HLA-DQA1 and DQB1 alleles with alolpecia areata in Chinese Hans

Accumulative evidences have shown that certain HLA loci are associated with alopecia areata (AA), but with existing differences in ethnic distribution. No report has ever been published about this in Chinese Hans. To investigate whether HLA-DQA1 and DQB1 alleles are associated with AA, and the correlation of the HLA profile with age of onset, severity, duration of current attack, recurrence and family history of AA in Chinese Hans. The polymerase chain reaction–sequence-specific primer (PCR-SSP) method was used to analyze the distribution of HLA-DQA1 and DQB1 alleles in 192 patients with AA and 273 healthy controls in Chinese Hans. The significant increased frequencies of HLA-DQA1*0104 (OR=3.38, P _c<0.001), HLA-DQB1*0604 (OR=5.17, P _c=0.006) and HLA-DQA1*0606 (OR=3.73, P _c<0.001) were observed in patients compared with controls. The DQA1*0104-DQB1*0604, DQA1*0104-DQB1*0606, and DQA1*0302-DQB1*0606 were found as high-risk haplotypes in developing AA in this study. HLA-DQA1*0104 (OR=5.31, P _c < 0.001) and -DQB1*0604 (OR=5.56, P _c=0.015) were more prevalent only in AA patients with long duration than controls. The frequencies of HLA-DQB1*0604 (OR=5.42, P _c=0.009) and -DQB1*0606 (OR=4.11, P _c<0.001) were obviously increased in patients less than 50% scalp hair loss. No locus was merely associated with early onset, severe involvement, recurrence and a positive family history of AA. This study demonstrated the positive association of HLA-DQA1 and DQB1 alleles and haplotypes with AA. There may be differences in genetic background in patients with different duration.