HLA-DRB1等位基因与广东汉族人群甲真菌病的相关性研究

 目的:探讨人类白细胞抗原HLA DRB1等位基因与广东汉族人群甲真菌病的关联性。方法：纳入64例广东汉族甲真菌病患者(包括10例红色毛癣菌甲癣患者)以及64例健康对照者,采用聚合酶链式反应-序列特异性引物（PCR-SSP）技术,对研究对象全血基因DNA进行HLA DRB等位基因分型,比较等位基因频率,分析甲真菌病与HLA基因多态性的关系。结果：甲真菌病患者HLA-DRB1*10基因频率高于健康对照组（ X²=5.10,P<0.05）。红色毛癣菌感染的甲癣患者组HLA DRB1*12基因频率低于健康对照组（  X²=4.70,P<0.05）。结论：HLA-DRB1*10等位基因可能是广东汉族人群甲真菌病遗传易感基因,而HLA-DRB1*12等位基因可能是红色毛癣菌感染的甲真菌病患者的保护性基因,HLA基因多态性与甲真菌病的发生可能存在遗传免疫关联性。     

Linkage and association of HLA class II genes with vitiligo in a Dutch population

BACKGROUND: Serological typing of HLA has shown discrepancies in HLA associations with vitiligo in different ethnic populations. OBJECTIVES: To perform genotyping of HLA class II genes on a Dutch vitiligo population in order clearly to identify susceptible and protective HLA alleles in vitiligo. METHODS: HLA typing was carried out by amplifying genomic DNA by polymerase chain reaction (PCR) followed by dot-blot hybridization with sequence-specific oligonucleotides (SSO). Fifty Dutch vitiligo probands, and their parents (150 individuals) and 204 healthy controls were studied. RESULTS: Family-based case-control association studies and linkage disequilibrium analysis showed the linkage and association of DRB4*0101 allele with vitiligo (P(c) = 0.0016, relative risk = 2.21). The family-based association study also provided evidence for linkage and association of DQB1*0303 allele with vitiligo (chi(2) = 7.36, P = 0.006). We measured the clinical relevance of the test by calculating the prevalence corrected positive predictive values (PcPPV). The PcPPV of disease for the DRB4*0101 allele was 0.017 and for the DRB4*0101/0101 genotype was 0.0358. In other words, a DRB4*0101/0101 genotype carries a 3.58% risk of developing vitiligo. CONCLUSIONS: Both DRB4*0101 and DQB1*0303 alleles provide significant susceptibility for vitiligo.     

Association of HLA alleles and haplotypes with vitiligo in Moroccan patients: a case–control study

The aim of this study was to identify HLA class II alleles that may be involved in vitiligo genetic susceptibility in the Moroccan population and to determine susceptible and protective HLA alleles/haplotypes in vitiligo. One-hundred unrelated vitiligo patients and 300 healthy unrelated controls were studied for HLA class II alleles by polymerase chain reaction-sequence-specific primers. The phenotypic frequency of DRB1*07 (OR = 2.23, p _c = 0.014) was significantly higher, while that of DRB1*03 (OR = 0.40, p _c = 0.014) was significantly lower in patients than in controls. Haplotype DRB1*07–DQB1*02 (OR = 2.25, p _c = 0.024) was positively associated with vitiligo patients, while haplotype DRB1*03–DQB1*02 (OR = 0.35, p _c = 0.012) was negatively associated with this group. Vitiligo patients with positive family history and negative anti-thyroid peroxidase antibody (anti-TPO) have an extremely high phenotype frequency of DRB1*07–DQB1*02 haplotype (OR = 2.91, p _c = 0.048 and OR = 2.62, p _c = 0.00475, respectively). DRB1*03–DQB1*02 (OR = 0.32, p _c = 0.048 and OR = 0.38, p _c = 0.048, respectively) was negatively associated with patients without a family history and negative anti-TPO. This study demonstrated the positive association of HLA class II alleles and haplotypes with vitiligo in the Moroccan population. There may be differences in HLA haplotypes distribution in patients according to family history and anti-TPO profile.     

华东地区汉族HLA-Ⅱ类基因与白癜风临床特征的相关性

目的：探讨华东地区汉族HLA-Ⅱ类基因与白癜风临床特征的相关性。方法：采用聚合酶链反应-序列特异性寡核苷酸探针(PCR-SSOP)方法检测华东地区汉族白癜风患者HLA-DRBl、DQAl和DQBl位点的等位基因，使用SPSS 10．0统计软件分析。结果：HLA-DQAl ^*0103与伴发内分泌疾病的患者有显著正相关，DRB l^*09与C4降低的患者明显负相关。按临床类型分析，发现局限型与DRBI*09和DQAl*03正相关，非节段型与DQAl*03正相关。结论：在华东地区汉族人群中，白癜风的临床特征与HIA-Ⅱ类基因有一定的相关性。     

Association of HLA loci alleles and antigens in Saudi patients with vitiligo

HLA complex is composed of several closely linked loci, each containing several alleles, yielding a high expression of polymorphism. Vitiligo, a commonly acquired dermatological disorder, has been associated with different HLA antigens in different ethnic groups. In this study, HLA classes I (HLA-A, B, and C) and II (HLA-DR, DQ) antigens/alleles were analyzed in a group of 80 Saudi subjects consisting of vitiligo patients (40) and matched controls (40). The frequency of antigens of various HLA loci was tested using two-stage microcytotoxicity assays, while the frequency of alleles of HLA-DR was screened by polymerase chain reaction/sequence specific primers (PCR/SSP) method. The frequencies of HLA-B7, B15, Bw6, Cw6, Cw7, and DRB4*010101 were found to be significantly higher in vitiligo patients compared to controls [P = 0.029, 0.015, 0.033, 0.009, 0.043, and 0.015, respectively, with relative risk (RR) ≥ 3, etiologic fraction (EF) ≥ 0.4]. On the other hand, HLA-A9, B5, DQ1, and DRB3*010101 were significantly decreased in vitiligo patients compared to healthy Saudis [P = 0.008, 0.004, 0.028, and 0.04, respectively, with RR < 1 and preventive fraction (PF) < 0.5]. Among the patients, the highest allele frequency was noted for DRB4*010101(70%), while in controls it was for DRB3*010101 (72.5%). These results for antigens and allele frequency of various HLA Loci in vitiligo patients and control subjects suggested that HLA-B7, Bw6, Cw6, Cw7, and DRB4*010101 could be susceptible to vitiligo, while HLA-A9, B5, DQ1, and DRB3*010101 might be negatively associated with the development of vitiligo in Saudis.     

Association between HLA-DRB1 polymorphisms and pemphigus vulgaris: a meta-analysis

Background Several studies have reported that HLA‐DRB1 may be correlated with pemphigus vulgaris (PV), but most have been based on small samples and the results remain inconsistent and unclear. Objectives To investigate the correlation between DRB1 and PV by a meta‐analysis of case–control/nonfamily studies. Methods PubMed, Wiley Online Library, ScienceDirect, Google Scholar, Cochrane Library, Chinese National Knowledge Infrastructure and Wanfang databases were searched for studies including: (i) ‘pemphigus’; and (ii) ‘human leukocyte antigen’, ‘HLA’, ‘major histocompatibility complex’, ‘MHC’ or ‘DRB1’. Eighteen selected studies were used in meta‐analyses to evaluate DRB1 alleles and phenotypes by calculating the respective odds ratios (ORs) and 95% confidence intervals (CIs). Stratified meta‐analyses and meta‐regression analysis were also conducted. Results The frequencies of three genotypes (allele and phenotype, respectively) were significantly increased in PV: DRB1*04 [P‐value for comparability (Pc) < 0·00001, OR 3·61, 95% CI 2·28–5·71; Pc = 0·0002, OR 4·14, 95% CI 1·98–8·65], DRB1*08 (Pc = 0·03, OR 2·25, 95% CI 1·07–4·70; Pc = 0·0003, OR 2·46, 95% CI 1·51–4·01) and DRB1*14 (Pc < 0·00001, OR 6·47, 95% CI 4·52–9·26; Pc < 0·00001, OR 9·68, 95% CI 4·47–20·98). Three others (allele and phenotype, respectively) were significantly decreased in PV: DRB1*03 (Pc < 0·00001, OR 0·28, 95% CI 0·19–0·41; Pc = 0·0001, OR 0·25, 95% CI 0·12–0·51), DRB1*07 (Pc = 0·004, OR 0·45, 95% CI 0·26–0·78; Pc = 0·0002, OR 0·27, 95% CI 0·14–0·54) and DRB1*15 (Pc = 0·001, OR 0·35, 95% CI 0·18–0·66; Pc = 0·002, OR 0·32, 95% CI 0·16–0·65). Ethnicity partially explained the heterogeneity of DRB1*07, DRB1*08 and DRB1*14 phenotypes. Conclusions Our findings suggest that DRB1*04, DRB1*08 and DRB1*14 are statistically significant susceptibility factors for PV. Conversely, DRB1*03, DRB1*07 and DRB1*15 may be negatively associated with PV. Specific HLA‐DRB1 types may influence the susceptibility or resistance to PV, which needs further investigations.     

Association between psoriasis vulgaris and MHC-DRB, -DQB genes as a contribution to disease diagnosis

We analyzed 100 control individuals and 60 patients with psoriasis vulgaris from the population of Campinas, Brazil. Typification of class II HLA alleles (HLA-DRB1-5 and -DQB1) was carried out through the DNA/PCR/SSP at medium and high resolution. DNA was extracted through a salting-out procedure: 13 DRB1 alleles, 3 DRB3 alleles, 1 DRB4 allele, 2 DRB5 alleles, and 5 DQB1 alleles were identified at a medium resolution using the PCR/SSP, and 45 DRB1 alleles were identified at a high resolution in analyzed patients. Results showed associations with psoriasis vulgaris: positive associations HLA-DRB3*02 (p < 0.05, chi(2) = 5.10, RR = 2.14); HLA-DRB1*0102 alleles (p < 0.05, RR = 5.44). Negative associations were found for HLA-DRB4*01 (chi(2) = 3.23, RR = 0.55) and HLA-DRB1*1302 alleles (p < 0.05, RR = 0.23). The haplotypes revealed positive association for HLA-DRB1*0102/DQB1*05 (p < 0.05, RR = 5.44) and HLA-DRB1*0701/DQB1*03 alleles (p < 0.02, RR = 9.00). These findings suggest a possible association of the DRB1 allele with the group of patients showing an early onset of the illness, as well as an association with haplotypes HLA-DRB1*0102/DQB1*05 and HLA-DRB1*0701/DQB1*03.     

Association of HLA loci alleles and antigens in Saudi patients with vitiligo

HLA complex is composed of several closely linked loci, each containing several alleles, yielding a high expression of polymorphism. Vitiligo, a commonly acquired dermatological disorder, has been associated with different HLA antigens in different ethnic groups. In this study, HLA classes I (HLA-A, B, and C) and II (HLA-DR, DQ) antigens/alleles were analyzed in a group of 80 Saudi subjects consisting of vitiligo patients (40) and matched controls (40). The frequency of antigens of various HLA loci was tested using two-stage microcytotoxicity assays, while the frequency of alleles of HLA-DR was screened by polymerase chain reaction/sequence specific primers (PCR/SSP) method. The frequencies of HLA-B7, B15, Bw6, Cw6, Cw7, and DRB4*010101 were found to be significantly higher in vitiligo patients compared to controls [P = 0.029, 0.015, 0.033, 0.009, 0.043, and 0.015, respectively, with relative risk (RR) > or = 3, etiologic fraction (EF) > or = 0.4]. On the other hand, HLA-A9, B5, DQ1, and DRB3*010101 were significantly decreased in vitiligo patients compared to healthy Saudis [P = 0.008, 0.004, 0.028, and 0.04, respectively, with RR < 1 and preventive fraction (PF) < 0.5]. Among the patients, the highest allele frequency was noted for DRB4*010101(70%), while in controls it was for DRB3*010101 (72.5%). These results for antigens and allele frequency of various HLA Loci in vitiligo patients and control subjects suggested that HLA-B7, Bw6, Cw6, Cw7, and DRB4*010101 could be susceptible to vitiligo, while HLA-A9, B5, DQ1, and DRB3*010101 might be negatively associated with the development of vitiligo in Saudis.     

Genotyping of HLA-I and HLA-II alleles in Chinese patients with paraneoplastic pemphigus

BACKGROUND: Class I and class II HLA genes are thought to play a role in the immunopathogenesis of bullous dermatoses such as pemphigus vulgaris and pemphigus foliaceus, but we know little about the genetic background of paraneoplastic pemphigus (PNP) in Chinese patients. OBJECTIVES: To identify class I and class II HLA alleles by genotyping in Chinese patients with PNP, and to find out the possible association between HLA alleles and disease susceptibility. METHODS: Nineteen Chinese patients with PNP were enrolled in this study. HLA-A, B, C, DRB1 and DQB1 alleles were typed by polymerase chain reaction and a colour-coded sequence-specific oligonucleotide probes method. RESULTS: The frequencies of HLA-B*4002/B*4004, B*51, B*52, Cw*14, DQB1*0301, DRB1*08 and DRB1*11 were relatively prevalent in Chinese Han patients with PNP in comparison with normal controls. After correction for multiple comparisons, Cw*14 remained statistically significant, and the other alleles were unremarkable in these patients. CONCLUSIONS: The genetic background predisposing to PNP may be different in patients from various races and areas. HLA-Cw*14 may be the predisposing allele to PNP in Chinese patients, which is different from the predisposing allele in French patients with PNP and the alleles predisposing to pemphigus vulgaris and pemphigus foliaceus.     

Association of HLA-DQA1 and DQB1 genes with vitiligo in Chinese Hans

BACKGROUND: Vitiligo is an acquired depigmentary disorder of the skin and hair which results from selective destruction of melanocytes. Serological typing and genotyping of human leukocyte antigen (HLA) have shown discrepancies in HLA associations with vitiligo in different ethnic populations. METHODS: Polymerase chain reaction sequence-specific primer (PCR-SSP) method was used to analyze the distribution of HLA-DQA(1) and -DQB(1) alleles among 187 patients with vitiligo and 273 healthy controls through Epi Info version 6 package (Centers for Disease Control and Prevention, Atlanta, GA, USA). RESULTS: The frequencies of HLA-DQA1*0302 (OR = 1.98, P(c) < 0.01), -DQB1*0303 (OR = 3.14, P(c) < 0.001), and -DQB1*0503 (OR = 3.36, P(c) < 0.05) alleles were significantly increased in patients with vitiligo compared with controls, and HLA-DQA(1)*0501 (OR = 0.40, P(c) < 0.01) allele frequency was highly decreased. HLA-DQA1*0302 (OR = 5.19, P(c) < 0.001), -DQA1*0601 (OR = 2.95, P(c) < 0.05), -DQB1*0303 (OR = 4.50, P(c) < 0.001), and -DQB1*0503 (OR = 6.69, P(c) < 0.001) alleles were positively associated, whereas HLA-DQA1*0501 (OR = 0.05, P(c) < 0.001) allele was negatively associated with childhood vitiligo patients, and HLA-DQB1*0303 (OR = 2.76, P(c) < 0.001) allele was positively associated with adult vitiligo patients compared with controls. The frequency of HLA-DQB1*0303 (OR = 3.72, P(c) < 0.001) allele was significantly increased in localized vitiligo patients vs. controls, whereas HLA-DQA1*0302 (OR = 2.47, P(c) < 0.01), -DQB1*0303 (OR = 2.67, P(c) < 0.01), and -DQB1*0503 (OR = 4.46, P(c) < 0.01) allele frequencies were significantly increased and -DQA1*0501 (OR = 0.27, P(c) < 0.01) allele frequency was highly decreased in generalized vitiligo patients. CONCLUSIONS: HLA-DQA1*0302, -DQA1*0601, -DQB1*0303, and -DQB1*0503 alleles could be susceptible alleles of vitiligo, while HLA-DQA1*0501 allele could be a protective allele in Chinese Hans. There may be different genetic backgrounds between vitiligo patients of childhood and adult, localized and generalized.     

HLA alleles and amino-acid signatures of the peptide-binding pockets of HLA molecules in vitiligo

Vitiligo is a depigmenting disorder of the skin that is characterized by the loss of functional melanocytes from the lesional sites. Although the exact etiology is not understood, autoimmunity is thought to be a crucial deterministic factor. A recurring theme of several autoimmune disorders is the aberrant presentation of self-antigens to the immune system, which triggers downstream perturbations. Here we examine the role of alleles of HLA class I and class II loci to delineate vitiligo manifestation in two distinct populations. Our studies have identified three specific alleles, HLA-A*33:01, HLA-B*44:03, and HLA-DRB1*07:01, to be significantly increased in vitiligo patients as compared with controls in both the initial study on North Indians (N=1,404) and the replication study in Gujarat (N=355) cases, establishing their positive association with vitiligo. Both generalized and localized vitiligo have the same predisposing major histocompatibility complex alleles, i.e., B*44:03 and DRB1*07:01, in both the populations studied, beside the differences in the frequencies of other alleles, suggesting that localized vitiligo too may be an autoimmune disorder. Significant differences in the amino-acid signatures of the peptide-binding pockets of HLA-A and HLA-B α-chain and HLA-DR β-chain were observed between vitiligo patients and unaffected controls.     

SLE患者抗U1 RNP抗体与HLA-Ⅱ类基因的相关性分析

目的 探讨云南汉族系统性红斑狼疮（SLE）患者抗U1RNP抗体与HLA－DRB1、DQA1、DQB1等3位基因及单体型的相关性。方法 采用多聚酶链反应－序列特异性引物（PCR－SSP）技术对63例云南汉族SLE患者进行DRB1、DQA1、DQB1基因分型。结果 抗U1RNP抗体阳性的SLE病人中DQA1＊0101及DR15－DQA1＊0102－DQB1＊0601单体型频率亦显著增高（P＝0．040，P＝0．000）。结论 云南汉族SLE抗U1RNP抗体的产生与DQA1＊0101等位基因及DR15－DQA1＊0102－DQB1＊0601单体型相关。     

Variation at HLA‐DPB1 is associated with dermatomyositis in Chinese population

Dermatomyositis (DM) is a polygenic disorder characterized by inflammation of skeletal muscle and skin. To date, the exact etiopathogenesis of DM remains elusive. To explore the genetic basis of DM, we conducted genome‐wide genotyping analysis of 127 patients and 1566 healthy controls by Illumina Human OmniZhongHua‐8 BeadChips in the Chinese Han population. We investigated whether the three SNP ( rs7750458 , rs9501251 and rs9500928 ) at 6p21.32 in the HLA‐DPB1 gene were significantly associated with DM (P < 5 × 10^?8) and identified two susceptibility loci at 7q34 (PIP, rs9986765 , P = 7.45 × 10^?7, odds ratio [OR] = 2.71) and 10q24.2 (CPN1, rs3750716 , P = 9.04 × 10^?7, OR = 4.39) with suggestive evidence. We imputed 6674 classical human leukocyte antigen (HLA) alleles, amino acids and SNP from the discovery dataset, and stepwise analysis revealed that HLA‐DPB1*17 in class II HLA genes were significantly associated with DM susceptibility. This study represents the first genome‐wide association study (GWAS) of DM in the Chinese Han population. For the first time, HLA‐DPB1 was found to be associated with DM in this population. Moreover, we identified two novel suggestive susceptibility loci (PIP and CPN1) and confirmed four previously reported genes (DMB, DQA1, DQB1 and DRB1) having potential associations with DM in the Chinese Han population. Our GWAS results in this population should provide important information regarding the genetic etiopathogenesis of DM and facilitate the development of new therapies for the treatment of DM and the prevention of DM progression.     

华东地区汉族斑秃与HLA-DRB1*03、*04、*11基因多态性的关联研究

目的 探讨中国华东地区汉族人群HLA-DRB1基因与斑秃发病、临床特点的关系。方法 采用序列特异性引物PCR（PCR-SSP）技术对已确诊为斑秃的158例和正常人对照组172例进行HLA-DRB1基因多态性分析。并比较斑秃患者不同发病年龄、发病次数、病程、家族史及严重程度与HLA-DRB1基因的关联性。结果 斑秃组HLA-DRB1*03、HLA-DRB1*11等位基因频率与对照组差异无统计学意义。斑秃组HLA-DRB1*04（OR = 1.99,Pc = 0.01）等位基因频率明显高于对照组。与正常人对照组比较,斑秃晚发组（发病年龄 > 16岁）（OR = 1.94,Pc = 0.02）、斑秃复发组（发病次数 > 1）和初发组（OR = 2.49、Pc = 0.02,OR = 1.83、Pc = 0.04）、病程 > 1年的患者（OR = 2.94,Pc = 0.01）、无家族史的患者（OR = 1.97,Pc = 0.02）、严重斑秃患者（OR = 3.53,Pc = 0.00）HLA-DRB1*04等位基因频率均显著升高。结论 中国华东地区汉族人群HLA-DRB1*04等位基因与斑秃发病、临床分型显著相关。     

Correlation between HLA and pityriasis rosea susceptibility in Brazilian blacks

Objectives The human leucocyte antigen (HLA) has been related to susceptibility factors in several diseases. This study aimed to determine the potential genetic susceptibility of patients with pityriasis rosea (PR) through HLA molecular typing analysis. Methods The method of choice was polymerase chain reaction with sequence‐specific primers (PCR‐SSP) using low‐resolution typing kits, with determination of the alleles class I (HLA‐A, HLA‐B and HLA‐C) and class II (HLA‐DRB1, DRB3, DRB4, DRB5 and DQB1) performed in 30 Afro‐Brazilian PR‐diagnosed patients and 45 healthy individuals as the control group (PR‐C). Results Analysis of the HLA typing results showed that the relative risk (RR) of 4.00 [95% confidence interval (95% CI) 1.20–13.28, two‐tailed P = 0.018] for allele HLA‐DQB1*04 class II, detected in 33.3% of PR patients, was significant. By contrast, in the control group only 11.1% of subjects had that allele. Three out of six B*51 alleles and three out of six B*53 alleles detected in PR patients were found, together with the allele DQB1*04. Conclusion We suggest that alleles DQB1*04 may be involved in the genetic susceptibility of PR based on the significant predominance of those alleles observed in the black PR patients. We also recommend that more studies are conducted on populations of other ethnic origins, preferentially with higher resolution techniques of DNA typing.     

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.     

Genetic association of HLA-DQB1 and HLA-DRB1 polymorphisms with alopecia areata in the Italian population

Background Alopecia areata (AA) is a multifactorial disease characterized by hair loss especially from the scalp. As for other autoimmune conditions, the major histocompatibility complex (HLA) region is associated with AA susceptibility. Objective To provide evidence for the association of specific HLA‐DQB1 and HLA‐DRB1 alleles with AA in an Italian population, using a case–control approach. Methods We performed a case–control study to investigate whether HLA‐DQB1 and ‐DRB1 alleles predispose to AA in the Italian population. HLA class II typing was performed in 85 patients with AA and 210 healthy controls from the same ethnic group. Results An increased frequency of DQB1*03, coding for DQ7 heterodimers, and a decreased rate of the DQB1*06 allele were observed in patients when compared with controls; the greatest and significant difference was in the group of cases with a more severe phenotype [AA > 50% patients (more than 50% hair loss) vs. controls, P = 4·5 × 10^?3, P_c = 0·031, odds ratio (OR) 2·01, 95% confidence interval (CI) 1·22–3·31 and P = 2·5 × 10^?3, P_c = 0·017, OR 0·22, 95% CI 0·07–0·72, respectively]. DQB1*03, serologically related to DQ8 or coding for DQ9 molecules, was not associated with AA susceptibility. Out of all patients, 65·9% carried DQ7 heterodimers compared with 49·5% of the controls (P = 7·3 × 10^?3, OR 1·97, 95% CI 1·17–3·32) and DQ7 prevalence rose to 76·3% in patients with AA > 50% (P = 1·7 × 10^?3, OR 3·28, 95% CI 1·48–7·27). No significant difference was found in the distribution of DRB1 variants or phenotypes among cases and controls. Conclusion Our data show a correlation between the HLA‐DQB1 locus and the occurrence of AA in Italy supporting DQB1*03(DQ7) as a predisposing allele for the disease and the relevance of the HLA genetic test in the clinical management of AA.     

Association between HLA-B*58:01 allele and severe cutaneous adverse reactions with allopurinol in Han Chinese in Hong Kong

Background Allopurinol has been reported as a common cause of severe cutaneous adverse reactions (SCARs). Recent studies in various populations suggest that HLA‐B*58:01 is a strong genetic marker for allopurinol‐induced SCAR, especially in populations with a high frequency of HLA‐B*58:01. Objectives To confirm the association link between HLA‐B*58:01 and hypersensitivity reactions attributed to allopurinol use in Han Chinese patients in Hong Kong. Methods We performed a case–control study to investigate whether the HLA‐B*58:01 allele predisposes to allopurinol‐induced SCAR in Han Chinese patients in Hong Kong. The HLA‐B*58:01 genotyping was performed in 20 patients with allopurinol‐induced SCAR or erythema multiforme major (EMM; n = 1) and in 30 patients tolerant to allopurinol. Results All of the 19 patients with allopurinol‐induced SCAR examined but not the patient with EMM carried HLA‐B*58:01 whereas only four (13%) of the control patients had this allele. The positive rate of the HLA‐B*58:01 was significantly higher in the cases than in the allopurinol‐tolerant control group [odds ratio (OR) 123·5, 95% confidence interval (CI) 12·8–1195·1; P < 1 × 10^?4] and was even higher after removal of the patient with EMM (OR 229·7, 95% CI 11·7–4520·4). The sensitivity and specificity of the HLA‐B*58:01 allele for prediction of allopurinol‐induced SCAR were 100% and 86·7%, respectively. Conclusions This study confirmed the strong association between the HLA‐B*58:01 and allopurinol‐induced SCAR in Hong Kong Han Chinese patients. A screening test for the HLA‐B*58:01 allele should effectively reduce the risk for allopurinol‐induced SCAR in Chinese populations.     

Association of HLA subtype DRB10407 in Colombian patients with actinic prurigo

BACKGROUND: Human leukocyte antigen (HLA) DRB1*0407 had been associated with actinic prurigo in different populations. This class II HLA-DR subtype had not been studied in Colombia. OBJECTIVE: The objective of this study was to establish whether there was an association of actinic prurigo with HLA DR in a Colombian population. MATERIALS AND METHODS: Forty patients with a clinical diagnosis of actinic prurigo and 40 healthy subjects, paired by age, sex and birthplace, were studied. HLA typing for HLA DRB1 and DRB1*04, if necessary, was performed by the PCR-SSP method using blood samples. RESULTS: A high frequency of HLA DRB1*0407 was found in the patients (97.5% vs. 30%; P<0.00001). The allelic frequency of HLA DRB1*0407 was 63.8% in the case group, and 14.5% in the controls (P<0.00001). In the control group, there was a higher frequency of the alleles DRB1*01 (14.5% vs. 1.25%; P=0.0027) and DRB1*13 (23.7% vs. 2.5%; P=0.00013). LIMITATIONS: The small number of controls does not allow us to drive conclusions about other HLA alleles. CONCLUSIONS: HLA subtype DRB1*0407, found in actinic prurigo patients in studies conducted in England, Scotland, Ireland and Mexico, was also associated in Colombian patients. This finding, concordant in patients from different ethnic groups, could be helpful in the diagnosis of this disease and probably important in its pathogenesis. DRB1*01 and DRB1*13 alleles were more frequent in controls than in patients; we do not know whether they play any role in the resistance to the disease.     

Human leucocyte antigen class II associations in chronic idiopathic urticaria

The major histocompatibility complex (MHC) acts as a marker for self during T-cell ontogeny and is associated with the pathogenesis of many autoimmune diseases. Recent investigations have shown about 30% of patients with chronic idiopathic urticaria (CIU) have IgG autoantibodies against the high-affinity IgE receptor, FcepsilonRI, or IgE. A link between MHC class II alleles and CIU has not been reported previously. DNA was extracted from blood of 100 Caucasian patients with CIU, and the MHC class II type determined using the polymerase chain reaction with sequence-specific primers, testing for DRB and DQB1 alleles. The frequency of alleles in CIU patients was compared with that found in 603 controls. Further human leucocyte antigen (HLA) typing on patient subsets, classified by the patients' responses to intradermal injection of autologous serum and their serum-induced histamine release from basophil leucocytes of healthy donors, was undertaken. HLA DRB1*04 (DR4) and its associated allele, DQB1*0302 (DQ8), are raised in CIU patients compared with a control population (P = 2 x 10-5 and P = 2 x 10-4, respectively). HLA DRB1*15 (DR15) and its associated allele, DQB1*06 (DQ6), are significantly less frequently associated with CIU. The HLA DRB1*04 association is particularly strong (corrected P = 3.6 x 10-6) for patients whose serum has in vivo and in vitro histamine-releasing activity. HLA class II typing is consistent with the concept that CIU is a heterogeneous disease, and supports an autoimmune pathogenesis in a subset of patients.