HLA-DQA1及DQB1等位基因与寻常型银屑病遗传易感性研究

目的 探讨HLA-DQA1和DQB1等位基因与汉族人寻常型银屑病遗传易感性。方法 利用聚合酶链反应-序列特异引物(PCR-SSP)法,对189例银屑病患者和273例健康人的HLA-DQA1和DQB1等位基因进行检测。结果 ①HLA-DQA1*0104和DQA1*0201与汉族人银屑病呈正相关性(Pc<0.05);DQA1*0501与汉族人银屑病呈负相关(Pc<0.001).②HLA-DQA1*0104、DQA1*0201和DQA1*0501等位基因与Ⅰ型银屑病发病有关。③HLA-DQA1*0104和DQA1*0201等位基因在有家族史和无家族史患者中的频率显着性增高。HLA-DQA1*0501仅在无家族史银屑病患者中显着性下降。结论 ①HLA-DQA1*0104和DQA1*0201可能是银屑病的易感基因或与易感基因相连锁;DQA1*0501等位基因可能具有阻止汉族人发生银屑病的作用。②有家族史和无家族史银屑病患者在其遗传背景上可能存在差异。     

Molecular analysis of HLA DP and DQ genes associated with dermatitis herpetiformis

HLA class II DQ and DP genes from dermatitis herpetiformis patients were amplified and analyzed using molecular probes and compared to those from celiac disease patients and to an HLA and ethnically matched control group. In dermatitis herpetiformis, as in celiac disease, the strongest association of disease was with the DQ subregion alleles DQB1*0201 and DQA1*0501 that are linked to the DRB1*0301 allele. DQB1*0201 determines the DQw2 serologic marker whereas DRB1*0301 determines the DRw17 serologic marker (formerly termed DR3). A DP subregion allele DPB1*0301 was increased and a constellation of DPB1 alleles that included DPB1*0202, *0901, and *1301 was decreased in dermatitis herpetiformis. DPB1*0101, an allele reported to be increased in celiac disease, was not increased in dermatitis herpetiformis. DP beta chains that lack a negatively charged amino acid residue at position 69 of the DP beta chain are significantly over-represented both in dermatitis herpetiformis and celiac disease patients with the DRw17, DQw2 haplotype, compared to healthy controls with that haplotype. These data favor a multigenic model for the contribution of HLA class II D region genes to dermatitis herpetiformis susceptibility. Further, they indicate that a specific DQ molecule, when present in combination with the product of one of several different DPB1 alleles, may contribute to susceptibility to the intestinal lesion, which is common to dermatitis herpetiformis and celiac disease.     

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.     

HLA-DQB1等位基因多态性与复发性尖锐湿疣的关系

【摘要】目的 研究HLA-DQB1等位基因DQB1*0501、DQB1*0502、DQB1*0201、DQB1*0402与复发性尖锐湿疣间的关系,为寻找尖锐湿疣的易感基因提供线索。方法 应用PCR-SSP技术检测84例复发性尖锐湿疣患者和107例正常人的HLA-DQB1等位基因DQB1*0501、DQB1*0502、DQB1*0201、DQB1*0402。结果 尖锐湿疣复发组DQB1*0501等位基因频率明显降低（8.3% vs 21.5%,P<0.05）,DQB1*0201等位基因频率明显降低（0% vs 9.3%,P<0.01）,另两等位基因在两组之间无明显差异,提示DQB1*0501与DQB1*0201与尖锐湿疣复发相关。结论 HLA 多态性可能是与尖锐湿疣复发有关的宿主遗传因素。     

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.     

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。     

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.     

特应性皮炎与HLA-DRB1 DQB1基因的相关性研究

目的探讨HLA-DRB1和DQB1位点基因与汉族特应性皮炎的相关性。方法用序列特异性引物-聚合酶链反应(PCR-SSP)方法,对59例特应性皮炎患者(来自27个家系)和60例正常对照者进行了HLA-DRB1和DQB1等位基因的分型,并分析了DRB1和DQB1基因在各组中的分布。结果特应性皮炎患者组DRB1*15,DR7,DQB1*0601等位基因频率较正常对照组增高(P<0.05);特应性皮炎患者组DQB1*0302频率较正常对照组降低(P<0.05)。特应性皮炎家系成员中对屋尘螨抗原皮试阳性者HLA-DR7等位基因频率较皮试阴性者均显著增高(P<0.05)。结论特应性皮炎的发病可能与DRB1*15,DR7,DQB1*0601相关;DQB1*0302对特应性皮炎的发病可能起保护作用。HLA-DR7在限定对屋尘螨抗原特异性IgE反应过程中起重要作用。     

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。     

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.     

Class II major histocompatibility complex typing across the ethnic barrier in pemphigoid gestationis. A study in Mexicans

BACKGROUND: Pemphigoid gestationis (PG), also called herpes gestationis, is a rare autoimmune disease of pregnancy or puerperium (estimated 1 out of 50,000 pregnancies among Caucasians). A previous series has demonstrated an association of PG with human leukocyte antigen (HLA)-DR3 or HLA-DR4 haplotypes. While these haplotypes are most commonly found in individuals of European ancestry, they have also been found in African-American patients affected with PG. PG has rarely been reported in other ethnic groups, and the HLA association in non-Europeans has not been examined. METHODS: We have characterized eight patients of Mexican ancestry who have PG by clinical, histologic, and immunofluorescence criteria. Class I and class II major histocompatibility complex (MHC) antigens were studied by standard microlymphocytotoxicity assays. Class II MHC antigens were further studied by polymerase chain reaction (PCR) amplification of HLA-DRB1, DQA, and DQB genes and allele-specific oligonucleotide hybridization. For comparison purposes, we used results obtained from a group of 100 ethnically matched healthy individuals. RESULTS: We found that all eight patients had the HLA-DR3/DR4 phenotype; all HLA-DR3 haplotypes were HLA-DRB1*0301, DQA1*0501, and DQB1*0201, whereas half of the HLA-DR4 haplotypes were from the DRB1*0401 subtype and the other half were DRB1 *0407. CONCLUSIONS: These results suggest that, in Mexicans, the genetic susceptibility for the development of PG is strongly influenced by the genetic admixture of Caucasian origin, and the role of class II MHC antigens in the pathophysiology of this disease is confirmed.     

Alterations in HLA-DP and HLA-DQ antigen frequency in patients with dermatitis herpetiformis

Dermatitis herpetiformis (DH) is associated with a markedly increased frequency of the HLA class II antigens DR3 and DQw2. To investigate a possible role of HLA-DP (or closely associated genes) in the pathogenesis of DH as well as to confirm the previously described alterations of HLA-DR3 and HLA-DQw2 antigen frequency, we have typed 43 patients with DH for HLA-DP, HLA-DQ, and HLA-DR antigens. All patients with DH had typical clinical and histologic features, as well as granular deposits of IgA at the dermal-epidermal junction by direct immunofluorescence. HLA-DR3 was expressed in 41 of 43 (95%) DH patients, whereas HLA-DQw2 was expressed in all 43 (100%). The overall distribution of HLA-DP antigens in patients with DH was significantly different from that seen in all controls and in HLA-DR3 and HLA-DQw2 controls (p less than 0.02). Examination of the frequency of individual DP antigens revealed that HLA-DPw1 was increased (42% of patients with DH vs 11% of all controls and 26% of DR3 positive controls), but this increase was not statistically greater than that expected due to the disequilibrium linkage of DPw1 with DR3/DQw2. Patients with DH, however, did have a statistically significant decreased frequency of DPw2 (14% of patients vs 31% of all controls and 41% of DR3 positive controls) (pc less than 0.05). Studies of three informative families demonstrated that the DPw2 genes of the DH patients were not present on the haplotype thought to carry a DH susceptibility gene (HLA-A1, HLA-B8, HLA-DR3, HLA-DQw2). A role of HLA-DP region genes in the pathogenesis of DH is further suggested by the observation that HLA-DPw1 was expressed in 82% (9 of 11) of DH patients with IgA antibodies against dietary antigens as compared with only 33% (4 of 12) of patients without IgA antibodies. HLA-DP genes or genes closely linked to them may be important in DH either as markers of the disease haplotype or by direct involvement in its pathogenesis.     

北方汉族衣原体引起盆腔炎患者与HLA-DQ相关性的研究

目的 探讨HLA-DQ基因与中国北方汉族衣原体引起盆腔炎的相关性。方法 采用聚合酶链反应/序列特异寡核苷酸探针(PCR-SSO)方法检测35例北方汉族衣原体引起盆腔炎患者的HLA-DQ等位基因。结果 与98例健康对照比较,盆腔炎患者HLA-DQA1*0501、HLA-DQB1*0301等位基因的频率明显增高,且与CHSP60抗体反应相关。结论 该结果可能为进一步揭示衣原体引起盆腔炎的易感基因和免疫遗传发病机制提供线索。     

A new extended haplotype Cw*0602-B57-DRB1*0701-DQA1*0201-DQB1*0201 associated with psoriasis in the Croatian population

In this study, we have analysed the distribution of HLA class II alleles and the extended haplotype HLA-Cw-B-DRB1-DQA1-DQB1 in Croatian patients with type I and type II psoriasis by hybridization with specific oligonucleotide probes. Type I psoriasis showed a significant association with the DRB1*0701 [P < 0.00001; relative risk (RR) = 5.83], DQA1*0201 (P < 0.00001; RR = 6.12), DQB1*0201 (P = 0.0006; RR = 3.29) and DQB1*0303 alleles (P = 0.0008; RR = 7.51). A negative correlation with type I disease was observed for the DQA1*0102 allele (P = 0.002; RR = 0.26). Type II psoriasis did not show any association with any class II alleles. The extended haplotype HLA-Cw*0602-B57-DRB1*0701-DQA1*0201-DQB1*0201 was present at a significantly higher frequency in type I patients (P < 0.00001; RR = 7.72). However, this haplotype was not detected at all in patients with type II psoriasis. In conclusion, the extended haplotype HLA-Cw*0602-B57-DRB1*0701-DQA1*0201-DQB1*0201 is a risk haplotype for type I disease in the Croatian population. This particular haplotype has not been reported previously in association with psoriasis in any other ethnic groups.     

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-DQA1和HLA-DQB1等位基因与皖籍汉族人群白癜风的相关性

目的 探讨HLA-DQA1、-DQB1等位基因与皖籍汉族人群白癜风的相关性。方法 采用聚合酶链反应-序列特异性引物(PCR-SSP)方法,检测白癜风患者的HLA-DQA1、-DQB1等位基因。结果 与正常人对照组比较,①白癜风患者HLA-DQA1*0302、-DQB1*0303、-DQB1*0503等位基因频率显著升高,HLA-DQA1*0501等位基因频率显著降低;②HLA-DQA1*0302、-DQA1*0601、-DQB1*0303、-DQB1*0503等位基因频率在儿童型白癜风患者中显著升高,HLA-DQA1*0501等位基因频率显著下降;而成人型白癜风患者HLA-DQB10303等位基因频率显著升高;③HLA-DQA1*0302、-DQB1*0303、-DQB1*0503等位基因频率在泛发型白癜风患者中显著升高,HLA-DQA1*0501等位基因频率显著下降;而局限型白癜风患者HLA-DQB1*0303等位基因显著升高。结论 HLA-DQA1*0302、-DQA1*0601、-DQB1*0303、-DQB1*0503、-DQA1*0501等位基因可能与白癜风相关,不同类型白癜风在其遗传背景上可能存在异质性。     

HLA-DQA1*0302、DQB1*0303与新疆维吾尔族白癜风的相关性研究

目的 探讨HLA-DQA1、DQB1等位基因与新疆维吾尔族白癜风相关性。方法 聚合酶链反应-序列特异性引物（PCR-SSP）检测300例维吾尔族白癜风患者HLA-DQA1*0302、DQB1*0303等位基因。结果 与300例维吾尔族正常人对照组相比,①白癜风患者DQA1*0302（20.5%比13.83%）、DQB1*0303（30.17%比13.33%）等位基因频率显著增高（P ＜ 0.01）;②HLA-DQA1*0302、DQB1*0303等位基因频率在成人型（发病年龄 ＞ 12岁）及儿童型（发病年龄≤12岁）的白癜风患者中均增高（P ＜ 0.01）;③HLA-DQB1*0303等位基因频率在有、无家族史的白癜风患者中均增高（P ＜ 0.01）,HLA -DQA1*0302等位基因频率在无家族史病例中显著增高（P ＜ 0.01）;④白癜风组儿童型和成人型两组间比较及有、无家族史两组间比较,DQA1*0302、DQB1*0303等位基因频率差异无统计学意义（P > 0.05）。 结论 HLA-DQA1*0302、DQB1*0303等位基因可能与新疆维吾尔族白癜风相关,儿童型和成人型及有、无家族史的白癜风在其遗传背景上可能存在异质性。     

Multiple basal cell carcinomas: no association with HLA-DRB, HLA-DQAI or HLA-DQBI in Swedish patients

Summary Many diseases with autoimmune features are associated with alleles of the human leucocyte antigen (HLA). However, few if any malignant disorders have reproducibly been shown to be HLA-associated. In three independent studies, using serological tissue typing techniques, an increase of the HLA class II specificity DR1 has been found in patients with multiple basal cell carcinomas. These observations prompted us to determine the frequencies of DRB1, DQA1, and DQB1 alleles by high-resolution genomic tissue-typing methods, including subdivision of the serological DR 1 specificity in the four sequence-defined alleles, DRB1*0101 to DRB1*0104, in 50 unrelated Swedish patients with a history of four or more basal cell carcinomas and 250 healthy controls. The frequency of DR1 was the same in patients and controls (18%). All DR1-positive patients and controls carried the DQA1* 0101 and DQBI*0501 alleles. Six of the nine DR1-positive patients were DRB1*0101-positive. one DRB1*0102 and two carried the DRB1*0103 allele. This distribution of DRB1*01 alleles did not differ from the one found in the controls. We conclude that genetic factors associated with the HLA class II region do not contribute significantly to the aetiology of multiple basal cell carcinomas.     

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.     

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.