Identification of a new HLA-DRB1*04 allele, DRB1*0437

In this report we describe the identification of a novel DRB1*04 allele, DRB1*0437, found in a Spanish individual. The routine HLA typing, in the context of bone marrow transplantation, by polymerase chain reaction-sequence-based typing (PCR-SBT) made possible the identification of this new allele. This allele is identical to DRB1*0402 except for a single nucleotide substitution at position 286 (A-->C), changing the encoded Isoleucine to a Leucine. The DRB1*0437 allele conserves the same two acidic residues at codons 70 and 71 that confer to DRB1*0402 its association to some autoimmune diseases.     

HLA-DQB1*0319, a novel HLA-DQB1 allele, shows strong haplotype association to HLA-DRB1*1102

The new human leukocyte antigen-DQB1*0319 allele was identified in a prospective bone marrow donor by sequence-based typing. This novel allele differs from the DQB1*0301 allele at nucleotide position 554 (C-->T), which results in a Thr to Ile amino acid exchange. The new allele shows a strong association to DRB1*1102, suggesting that the haplotype DRB1*1102-DQB1*0319 is quite common.     

Association of HLA-DRB1*1502-DQB1*0501 haplotype with susceptibility to systemic lupus erythematosus in Thais

In this study, we investigated the association of HLA-DRB1 and DQB1 with Thai patients with SLE. A highly significant increase in the frequency of DRB1*1502 and DQB1*0501 was found in SLE patients compared with normal controls. DRB1*1501 and DRB1*1602 were also slightly increased. In contrast, DRB1*1202 and DQB1*0301 were decreased, and DRB1*0406 and DRB1*1401 were not found in the patients' group. The haplotype analysis revealed that DRB1*1502 - DQB1*0501 was most strongly associated with SLE, and also suggested a primary role for DRB1 rather than DQB1. Taken together with the previous report which demonstrated the association of the same haplotype in Taiwan, our present observations strongly suggested that DRB1*1502 - DQB1*0501 is the major HLA haplotype that confers susceptibility to SLE in the South-east Asian populations.     

Characterization of a new HLA-DRB1*01 allele (HLA-DRB1*010203) in a Caucasian Italian family by using sequence-based typing

We report the identification of an HLA-DRB1*01 nucleotide sequence variant in three members of a Caucasian Italian family by using sequence-based typing. The nucleotide sequence of exon 2 observed in the new allele is identical to that of HLA-DRB1*010201 except in position 189 (codon 34) where the adenine of the consensus was replaced by a guanine and it was designated officially as HLA-DRB1*010203* by the WHO Nomenclature Committee.     

HLA-DRB1 and DQB1 genotypes in patients with insulin-dependent neonatal diabetes mellitus. A study of 13 cases

Insulin-dependent neonatal diabetes mellitus (NDM) is a rare form of diabetes with a heterogeneous genetic background. The HLA-DRB1 and DQB1 genotypes were determined for 13 patients with NDM, from 9 unrelated families. Four patients had permanent NDM (PNDM) and 9 patients had transient NDM (TNDM). No excess of HLA susceptibility markers for type 1 diabetes (IDDM) was observed in this series of patients, whatever the forms of diabetes PNDM or TNDM. Paternal isodisomy of chromosome 6 was observed in two TNDM cases. These observations are consistent with the current hypothesis that there is a recessive susceptibility gene, at least in the transient form of the disease, unlinked to the MHC locus on chromosome 6. Although established in a short series, our results do not support an additive role of IDDM1 in the progression of the disease.     

HLA-DMA and HLA-DMB alleles in German patients with type 1 diabetes mellitus

The HLA-DMA and HLA-DMB genes are located in the HLA-D region between DQ and DP. Four variants of DMA (DMA*0101-0104) and five of the DMB (DMB*0101-0105) have so far been identified. HLA-DM molecules are required in the process of peptide loading to HLA class II antigens, both regulating the dissociation of class II-associated invariant chain peptides (CLIP) and the subsequent binding of exogenous peptides to HLA class II molecules. In order to investigate the immunogenetic heterogeneity within the HLA-D susceptibility region, we analysed the distribution of DMA alleles in 125 patients with type 1 diabetes mellitus and 90 healthy controls, and of DMB alleles in 102 patients and 89 healthy controls. Patients and controls were all from central Germany. The polymerase chain reaction (PCR) amplified products were purified and separated on a 10% polyacrylamide gel electrophoresis. Among the four recognized DMA alleles, DMA*0102 was significantly less frequent (12% vs. 28.9%, P<0.01) in patients with type 1 diabetes mellitus. DMB*0101 (70.6% vs. 97.8%, P<5.5x10(-3)) was also reduced in frequency compared to controls. Comparing patients and controls positive for the type 1 diabetes high-risk markers we found a significant association between DMA*0102 and DQA*0501 (9.5% vs. 39.1%, P<0.02), as well as DMB*0101 and DQA*0501 (62.5% vs. 96.2%, P<0.03). In conclusion, DMA*0102 and DMB*0101 contribute to genetic protection to type 1 diabetes mellitus in individuals with high-risk DQA markers in the German population.     

HLA-DRB1*07 may have a susceptibility and DRB1*04 a protective effect upon the development of a sensitization to house dust mite Dermatophagoides pteronyssinus

BACKGROUND: IgE responses to house dust mite-derived allergens seem to be the most important in the development of atopic asthma and rhinitis, but it has been difficult to demonstrate genetic control of the IgE response to the allergens. OBJECTIVE: This study was undertaken to investigate the association between sensitization to house dust mite, D. pteronyssinus (DP), and genotypes of HLA-DRB1 alleles. METHODS: DNAs were extracted from two groups of unrelated Koreans: (1) 178 with sensitization to DP; and (2) 99 age-matched non-atopic controls. Genotypes of the HLA-DRB1 alleles were determined using polymerase chain reaction (PCR)-based methods. RESULTS: The frequency of HLA-DRB1*07 was significantly increased in the DP-sensitive subjects compared with the controls (15.7% vs 4.0%, P = 0.009). Conversely, the frequencies of HLA-DRB1*04 and *14 were decreased in the DP-sensitive subjects compared with the controls (27.5% vs 45.5%, P = 0.002; 13.5% vs 24.2%, P = 0.02). Of the DRB1*04 alleles, DRB1*0403 was significantly decreased in the DP-sensitive subjects compared with the controls (3.9% vs 13.1%, P = 0.005). No significant differences were found in the distributions of the other HLA-DRB1 alleles between the two groups. CONCLUSION: HLA-DRB1*07 may have a susceptibility, and DRB1*04 and DRB1*14 may have a protective effect, upon the development of a sensitization to DP.     

HLA-DRB1* and allergy to Parietaria: linkage and association analyses

In this study, we used the affected sibling-pairs approach to investigate the linkage of HLA (human leukocyte antigen)-DRB1* with phenotypes related to allergy to Parietaria, the most common pollinosis in Mediterranean countries. The study population consisted of 51 nuclear families (235 subjects). Linkage was detected with Parietaria skin test positivity (p < 0.01), presence of IgG and IgE antibodies specific for the major allergen Par o 1 (p < 0.020 and p < 0.025, respectively), and absence of Par o 1-specific IgE (p < 0.020).

High levels of Par o 1-specific IgG were associated with DRB1*1101 and/or DRB1*1104 (p < 0.0001 and p < 0.0119, respectively) in parents and probands. High levels of Par o 1-specific IgE were associated with DRB1*1104 in parents (p < 0.017) and with DRB1*1101 in probands (p < 0.0146). When siblings were categorized according to high/low total IgE levels (125 IU/ml and <125 IU/ml, respectively), high IgE antibody response was associated with DRB1*1104 in siblings with low total IgE (p < 0.034) and with DRB1*1101 in siblings with high total IgE (p < 0.05).

These results demonstrate that HLA-DRB1*, or genes in linkage disequilibrium, contributes to susceptibility to Parietaria allergy and that total IgE levels can discriminate population subsets where different alleles (at the HLA region or at loci in linkage disequilibrium) contribute to control allergen-specific IgE synthesis.     

HLA-DRB1基因多态性与克山病及其核心家系的关系研究

目的探讨HLA-DRB1基因多态性在我国北方克山病地区的分布特征及其与克山病核心家系的关联和连锁。方法采用聚合酶链反应-序列特异性寡核苷酸探针(polymerase chain reaction-sequence specific oligonucleotide probing,PCR-SSOP)技术,对118例克山病(Keshan disease,KD)患者HLA-DRB1基因进行分型,其中潜在型KD63例,慢型KD55例,65名正常人为对照;采用单倍型相对风险(haplotype based haplotype relative risk,HHRR)和传递不平衡检验(transmission disequilibrium test,TDT)方法对该基因在18个KD核心家系中的分布进行关联和连锁分析。结果(1)在KD患者和对照人群中,HLA-DRB1位点共检出13种等位基因;(2)DR7等位基因在KD组中的分布频率显著低于对照组(P<0.01,OR=0.1695);(3)DR7等位基因在慢型KD中的分布频率显著低于对照组(P<0.01,OR=0.091),而在潜在型KD中的分布频率与对照组比较差异无统计学意义;(4)DR15等位基因与KD显著关联(χ2=9.32,P<0.01),并与KD易感位点连锁(χ2=7.40,P<0.01)。结论KD可能存在遗传易感性,HLA-DRB1的DR7等位基因可能是KD保护性基因,携带DR7等位基因的KD患者可能不易发展为慢型KD,DR15等位基因可能与KD易感基因连锁。     

HLA-DRB1*0301等位基因与Graves病的关系

目的 探讨HLA-DRB1*0301等位基因在粤西湛江沿海地区Graves病(GD)发病中的作用.方法 选取65例初诊GD病人和正常对照50例并采用多聚酶链反应-序列特异性引物(PCR-SSP)技术检测HLA-DRB1*0301等位基因的表达频率.结果 初诊GD病人HLA-DRBl*0301等位基因的表达频率显著高于正常对照组(P＜0.005).结论 HLA-DRB1*0301等位基因可能是粤西湛江地区GD的易感基因.     

HLA-DRB1*0826 and HLA-DQB1*0627, two novel class II alleles identified in blood stem cell donors of Caucasian origin

This report describes two novel HLA class II alleles, HLA-DRB1*0826 and HLA-DQB1*0627, that have been identified in two unrelated voluntary blood stem cell donors of Caucasian origin. HLA-DRB1*0826 is characterized by a nucleotide substitution (G to T) in exon 2 at position 163, leading to an amino acid exchange from argenine to leucine. The donor phenotype is HLA-A*0301,*2902; B*3501,*4403; Cw*0401,*1601; DRB1*0101,*0826; DQB1*0402, *0501. The HLA-DQB1*0627 alleles contain a nucleotide substitution at position 184 (T to C) resulting in an amino acid exchange from tyrosine to histidine. Family segregation analysis revealed that the HLA-DQB1*0627 allele belongs to the haplotype A*0101, B*1517, Cw*0701, DRB1*1302, DQB1*0627. The donor phenotype is HLA-A*0101; B*0801,*1517; Cw*0701; DRB1*1302,*1501; DQB1*0602,*0627.     

HLA-DRB1* and allergy to Parietaria: linkage and association analyses

In this study, we used the affected sibling-pairs approach to investigate the linkage of HLA (human leukocyte antigen)-DRB1* with phenotypes related to allergy to Parietaria, the most common pollinosis in Mediterranean countries. The study population consisted of 51 nuclear families (235 subjects). Linkage was detected with Parietaria skin test positivity (p < 0.01), presence of IgG and IgE antibodies specific for the major allergen Par o 1 (p < 0.020 and p < 0.025, respectively), and absence of Par o 1-specific IgE (p < 0.020).High levels of Par o 1-specific IgG were associated with DRB1*1101 and/or DRB1*1104 (p < 0.0001 and p < 0.0119, respectively) in parents and probands. High levels of Par o 1-specific IgE were associated with DRB1*1104 in parents (p < 0.017) and with DRB1*1101 in probands (p < 0.0146). When siblings were categorized according to high/low total IgE levels (125 IU/ml and <125 IU/ml, respectively), high IgE antibody response was associated with DRB1*1104 in siblings with low total IgE (p < 0.034) and with DRB1*1101 in siblings with high total IgE (p < 0.05).These results demonstrate that HLA-DRB1*, or genes in linkage disequilibrium, contributes to susceptibility to Parietaria allergy and that total IgE levels can discriminate population subsets where different alleles (at the HLA region or at loci in linkage disequilibrium) contribute to control allergen-specific IgE synthesis.     

The human leucocyte antigen-DRB1*1302-DQB1*0609-DPB1*0201 haplotype may be a strong genetic marker for aspirin-induced urticaria

BACKGROUND: Urticaria/angioedema is a common aspirin-induced allergy; however, its pathogenic mechanism is not understood. OBJECTIVE: In order to uncover the genetic mechanism, we studied the associations of the human leucocyte antigen (HLA) genotypes in patients with aspirin-induced urticaria compared with aspirin-intolerant asthma and normal control in a Korean population. METHODS: Ninety-four aspirin-induced urticaria patients presenting urticaria/angioedema-induced by both ASA and NSAID (50 had underlying chronic urticaria) and showing positive responses on oral aspirin challenge test, 76 aspirin-intolerant asthmatics with positive responses on lysine-aspirin bronchoprovocation test, and 185 normal healthy controls were enrolled. HLA-DRB1, DQB1, and DPB1 genotypings were performed by direct DNA sequencing analysis. RESULTS: The allele frequencies of HLA-DRB1(*)1302 (18.1%) and HLA-DQB1(*)0609 (10.1%) in aspirin-induced urticaria were significantly higher than in aspirin-intolerant asthma (5.3%, P=0.0004; 2.0%, P=0.0024) and in normal controls (8.1%, P=0.0005; 3.2%, P=0.0008), and they remained significant after correcting for multiple comparisons. The patients with these two HLA markers had a significantly younger age than patients without, while no associations were found in with respect to atopic status, a history of previous allergic diseases, total IgE level, or presence of underlying chronic urticaria (P>0.05, respectively). In haplotype analysis, the HLA-DRB1(*)1302-DQB1(*)0609-DPB1(*)0201 was significantly higher in the aspirin-induced urticaria (8.0%) than in the aspirin-intolerant asthma (0.7%, P=0.0014) and normal controls (2.0%, P=0.0006). CONCLUSION: These findings suggest that the HLA-DRB1(*)1302-DQB1(*)0609-DPB1(*)0201 may be a strong genetic marker to determine the aspirin-induced urticaria phenotype.     

The critical amino acids of a nephritogenic epitope on human Goodpasture autoantigen for binding to HLA-DRB1*1501

BackgroundAnti-GBM disease is caused by autoimmunity to Goodpasture antigen on α3(IV)NC1 and had strong associations with HLA-DRB1*1501. Previous studies identified α3_127-148 (P14: TDIPPCPHGWISLWKGFSFIMF) as a T cell epitope. The present study was aimed to investigate the binding capacity of P14 to HLA-DRB1*1501 and the critical amino acids for this binding.MethodsA line of EBV-transformed human B cells homozygous for HLA-DRB1*1501 was used to detect the binding capacity of peptides to HLA-DRB1*1501 using flow cytometry analysis. P14 was sequentially truncated into 8 peptides with 15 amino acids to identify the core binding motif. A set of alanine substituted peptides of P14-2 was then synthesized to identify its critical residues for binding to HLA-DRB1*1501. The structure of HLA-DR2b-Peptide-TCR complex was constructed by modeling to analyze the interaction of each amino acids of P14-2 with the HLA-DR2b molecule.ResultsP14 could bind to HLA-DRB1*1501 expressed on B cell surface. The N-terminus of P14 was the core binding motif and the truncated peptide P14-2 (DIPPCPHGWISLWKG) _128-142 had the strongest binding capacity. After sequential amino acid substitution, we found the binding capacity of P14-2 was completely lost by the substitution of cysteine (C) ₁₃₂ and significantly decreased by the substitution of tryptophan (W) ₁₃₆, lysine (K) ₁₄₁, or glycine (G) ₁₄₂, but still at a high level. The modeling showed that (C) ₁₃₂ had a strong interaction with pocket 4 on the β chain of DR2b. Thus, C₁₃₂, W ₁₃₆, K₁₄₁, and G₁₄₂ were defined as the critical amino acid residues for the binding capacity of P14 to HLA-DRB1*1501.ConclusionWe identified α3_128-142 (DIPPCPHGWISLWKG) as the core binding motif of P14 to HLA-DRB1*1501 molecule. And the critical amino acid residues for this binding were further defined as C₁₃₂, W ₁₃₆, K ₁₄₁, and G ₁₄₂.     

HLA-DRB1基因多态性与慢性髓性白血病的相关性研究

目的:探讨HLA-DRB1等位基因多态性与慢性髓性白血病(CML)关联性。方法:采用序列特异性引物聚合酶链反应(PCR-SSP)DNA分型技术对762例慢性髓性白血病患者(男性492例,女性270例)及2 264例正常对照进行了HLA-DRB1基因分型。结果:正常人群的HLA-DRB1*15等位基因频率最高(17.25%),其次为DRB1*09(14.05%)、DRB1*12(11.73%)和DRB1*04(10.98%),DRB1*10等位基因频率最低(1.39%)。CML患者HLA-DRB1*08等位基因频率显著高于正常对照组(7.48%vs 5.39%,χ2=8.963,OR=1.023,P=0.004),男性患者的DRB1*08基因频率也明显高于正常对照(7.72%vs 5.39%,χ2=8.059,OR=1.025,P=0.007)。女性患者的DRB1*08基因频率也高于正常对照(7.04%vs 5.39%,χ2=0.115,OR=0.995,P=0.774),但没有统计学差异。结论:CML男性患者HLA-DRB1*08的表达明显高于正常人群,提示DRB1*08可能是男性CML患者的易感基因。     

HLA-DRB1 and MHC class 1 chain-related A haplotypes in Basque families with celiac disease

The contribution of HLA genes to the genetic risk for celiac disease (CD) has been known for a long time. Recent publications have pointed to the possibility that a second, independent susceptibility locus could be located in the same genomic region, and a triplet repeat polymorphism in exon 5 of the gene MHC class I chain-related protein A (MICA; located between TNFA and HLA-B) has been associated with several autoimmune disorders, including type 1 diabetes mellitus (DM1) and Addison's disease. On the other hand, a single amino acid change in exon 3 of MICA (M129V) has been shown to strongly reduce MICA binding to NKG2D, an activating natural killer receptor expressed also on T cells, and this could have significant effects on autoimmune reactions. In this study, we have analyzed the contribution of these polymorphisms to CD in 37 Basque families, and have constructed MICA-HLA-DRB1 haplotypes to determine whether MICA has an effect independent from the HLA class II conferred risk. In our population, HLA-DRB1*0301 was associated with an increased risk for CD, while HLA-DRB1*1501 conferred protection from the disease (OR: 7.38 and 0.06, respectively). On the other hand, MICA allele A4 was positively associated with the disease (OR: 4.69) whereas allele A9 showed a trend towards protection (OR: 0.18), although significance did not hold after correction. No association of the exon 3 biallelic polymorphism was observed. A positive allelic association was found for haplotypes A5.1-DRB1*0301 (associated with risk for disease), A4-DRB1*0301 and A6-DRB1*07. In view of our results, both HLA-DRB1 and MICA are associated with CD, but stratification analysis did not show any independent contribution of the MICA polymorphisms analyzed to CD risk. Besides, MICA allele A4 (also A5.1 was associated with risk for CD and other diseases) is in strong linkage disequilibrium with HLA-DRB1*0301. Finally, the major histocompatibility complex region's conferred susceptibility to CD, at least in Basque, is very similar to that observed for DM1, with shared risk and protective haplotypes.     

No association between HLA-DRB1 alleles and susceptibility to advanced stage endometriosis in a Korean population

BACKGROUND: The aetiological factors of endometriosis still remain poorly understood. While there is growing evidence that genetic and immunological factors play important roles in the pathogenesis of the disease, HLA-DRB1 alleles have been reported to be associated with the risk of endometriosis in Japanese populations. This study was performed to determine whether susceptibility to advanced endometriosis is also associated with HLA-DRB1 alleles in a Korean population, which is the closest ethnic group to Japanese. METHODS: We recruited 100 Korean patients with advanced endometriosis confirmed by surgical and histolological examinations. HLA-DRB1 genotyping was carried out in two steps. Low to intermediate resolution typing was performed by PCR sequence-specific oligonucleotide hybridization method, followed by high resolution typing utilizing group-specific amplification and PCR-single strand conformation polymorphism method. Distribution of HLA-DRB1 alleles was compared with that of 800 unrelated ethnically matched individuals as well as 108 healthy female subjects. RESULTS: Genotyping revealed that the distribution of HLA-DRB1 alleles in patients with advanced endometriosis was not different from that in the two control groups. CONCLUSIONS: The findings of the present study suggest that susceptibility of advanced endometriosis is not associated with HLA-DRB1 alleles in a Korean population, which is apparently not the case in the Japanese population.     

HLA-DRB1*0403 is associated with dominant protection against IDDM in the general Dutch population and subjects with high-risk DQA1*0301-DQB1*0302/DQA1*0501-DQB1*0201 genotype

Insulin-dependent (Type 1) diabetes mellitus (IDDM) is a genetically controlled T-cell mediated autoimmune disease. Recently, subtyping of HLA-DRB1*04 identified the HLA-DRB1*0403 allele to be associated with protection in Caucasoids with the highest risk heterozygous genotype DQA1*0301-DQB1*0302/DQA1*0501-DQB1*0201. Some studies confirmed this finding, but other reports were not consistent with a dominantly protective trait. We here report the frequency of HLA-DRB1*0403 in a large cohort (n=200) of Dutch patients with IDDM, their first-degree family members (n=370), and random controls (n=420) of the general population in The Netherlands. We found that HLA-DRB1*0403 is strongly associated with dominant protection against development of IDDM in unrelated subject, even in the context of the highest risk HLA-DQ phenotypes and HLA-DR4-DQB1*0302 (P < 0.0001).     

Identification of a new HLA-DRB1 allele (DRB1*0318) in three members of a Caucasian Spanish family

This communication reports the identification of a new allele HLA-DRB1*03 in three members of a Caucasian Spanish family. The new allele has been officially named HLA-DRB1*0318 by the World Health Organization Nomenclature Committee. The exon 2 sequence of this new allele is identical to that of DRB1*03011 except for the first nucleotide of codon 45. The nucleotide change (C replacing G) leads to the amino acid substitution of glycine to arginine (GGG-->CGG) at position 45. This position of the beta1 domain shows very little polymorphism among DRB1* alleles (nucleotide changes at this position have only been reported for DRB1*1436 and DRB1*0105) and locates in the vicinity of the highly polymorphic position 47, which is a constituent of the groove's pocket interacting with the amino acid position 7 of the antigen peptide. The familial study showed that the new allele was maternally transmitted into the HLA-A*3002, -B*1801, -Cw*0501, -DRB1*0318, -DRB3*0202, -DQB1*0201 haplotype. Interestingly, the two siblings of the family, which were HLA identical and suffered of insulin-dependent diabetes mellitus (IDDM), were carriers of the two HLA haplotypes (DRB1*03/DQB1*0201 and DRB1*04/DQB1*0302) reported as susceptibility markers to IDDM in Caucasians.