Ⅱ类人白细胞抗原等位基因与晚期肝脾型日本血吸虫病的相关性研究

目的　探讨Ⅱ类人白细胞抗原 (HLA-Ⅱ)基因多态性与晚期肝脾型日本血吸虫病的相关性。　方法　用聚合酶链反应-序列特异性引物 (PCR-SSP)技术对 46例晚期肝脾型日本血吸虫病患者 (实验组 )和 43例慢性日本血吸虫病患者 (对照组 )HLA-DRB1、DPA1、DQA1和DQB14个基因位点的等位基因进行分型。对两组间等位基因频率的差异进行 χ² 检验。　结果　实验组HLA-DRB1*04、DPA1*0103、DQA1*0601和DQB1*020 1等位基因频率明显高于对照组 ,而HLA-DQA1*0501和DQB1*0601等位基因频率明显低于对照组。　结论　HLA-DRB1*04、DPA1*0103、DQA1*0601和DQB1*0201等位基因 ,因其与晚期肝脾型日本血吸虫病呈显著的正相关 (P <0.0 5 )而可能是该病的遗传易感基因 ,而HLA-DQA1*0501和DQB1*0601等位基因与对该病存在抵抗性有关。     

The association between the genetic polymorphism of HLA-DQA1, DQB1, and DRB1 and serum alanine aminotransferase levels in chronic hepatitis C in the Chinese population

Background and Aim:  To investigate a possible association between HLA genes with serum alanine aminotransferase (ALT) levels and evaluate whether the HLA-DQA1, DQB1, and DRB1 genes could influence the development of liver damage in chronic hepatitis C.
Methods:  A total of 145 patients with chronic hepatitis C virus (HCV) infection (36 patients with persistently normal ALT values; 109 patients with elevated ALT levels) and 160 uninfected healthy controls were examined for HLA-DQA1, DQB1, and DRB1 molecules by using polymerase chain reaction–sequencing based typing (PCR-SBT).
Results:  Among the patients chronically infected with HCV, the frequencies of DQA1*0501, DQB1*0301, and DRB1*0401 alleles were significantly increased in the normal ALT group compared with those with abnormal ALT levels, whereas that of DQB1*0201 was significantly lower. As compared to uninfected healthy controls, DQA1*0501, DQB1*0301, and DRB1*0401 allele frequencies were also statistically higher in the normal ALT group, whereas that of DQB1*0201 was the inverse. The haplotype frequencies of DQA1*0301-DQB1*0301, DQA1*0501-DQB1*0301, and DRB1*1101-DQB1*0301 were found to be significantly higher in the normal ALT group. Multivariate logistic regression indicated that female sex, and the DQB1*0301 allele and DRB1*0401 allele were independently associated with normal ALT values, whereas DQB1*0201 allele was the inverse.
Conclusions:  These results suggest that particular HLA alleles may have an influence on the serum ALT level of chronic HCV infection as a host genetic factor in the Chinese population. The DQA1*0501, DQB1*0301, and DRB1*0401 alleles, and the DQA1*0301-DQB1*0301, DQA1*0501-DQB1*0301, and DRB1*1101-DQB1*0301 haplotypes seem to be associated with low hepatitis activity; whereas DQB1*0201 allele is closely correlated with the progression of liver injury in chronic HCV infection.     

中国人群1型糖尿病HLA-DQ基因多态性的Meta分析

目的　综合评价中国人群HLA DQ基因多态性与 1型糖尿病 (DM)的关联性。方法　以 1型DM组和健康对照组的各HLA DQ等位基因频数(基因型频数、单倍型频数 )分布的OR值为统计量,全面检索相关文献;应用Meta分析软件包REVMAN4. 2,在基因分型水平上,对各研究的结果进行一致性检验和数据合并,并评估发表偏倚。结果　等位基因DQA1* 0301、DQA1* 0501、DQB1* 0201、DQB1* 0303、DQB1* 0401和DQB1* 0604是中国人群 1型DM的危险基因 (均P<0. 05), 他们的合并OR值分别为2. 83、2. 90、4. 17、1. 65、2. 00和 3. 00;基因型 (或单倍型 )DQA1* 0301 /DQB1* 0201、DQA1* 0301 /DQB1*0302、DQA1* 0501 /DQB1* 0201、DQA1* 0301 /DQB1* 0201 /DRB1* 0301和DQB1* 0302 /DRB1* 0405是中国人群 1型DM的危险基因型(或单倍型,均P<0. 05),他们的合并OR值分别为 8. 95、3. 09、6. 01、6. 57和 14. 85。而等位基因DQA1* 0101、DQA1* 0102、DQA1* 0103、DQA1* 0104、DQA1* 0201、DQA1* 0401、DQA1* 0601、DQB1* 0301、DQB1* 0501、DQB1* 0503、DQB1* 0601和DQB1* 0602是中国人群 1型DM的保护等位基因(均P<0. 05),他们的合并OR值分别为 0. 47、0. 38、0. 21、0. 07、0. 44、0. 39、0. 44、0. 19、0. 33、0. 32、0. 42和 0. 28; 基因型     

Gene dose effect of the DQB1*0201 allele contributes to severity of coeliac disease

OBJECTIVE: Coeliac disease (CD) susceptibility has been shown to be associated with the HLA alleles DQA1*0501 and DQB1*0201. This HLA-associated risk has been estimated to account for 29-40% of the genetic component of CD. Conflicting data have been published on the gene dose effect of these HLA alleles on the risk and severity of CD. In this study the aim was to investigate the association between the number of HLA risk alleles and the severity of CD. MATERIAL AND METHODS: Fifty-four Finnish CD families, including 144 CD patients mainly diagnosed in adulthood (94.4%), were enrolled in the study. The association between the number of DQA1*0501 and DQB1*0201 alleles and villous atrophy, symptoms and laboratory parameters at the time of diagnosis, and the association with villous atrophy after one year of treatment on a gluten-free diet were studied. RESULTS: The homozygosity for the DQB1*0201 allele was associated with a more severe form of CD assessed by more severe villous atrophy (p=0.011), younger age (p=0.036), more severe diarrhoea (p=0.048) and a lower level of blood haemoglobin at the time of diagnosis (p=0.010). Furthermore, the homozygosity for the DQB1*0201 allele was associated with a slower recovery of villous atrophy after a gluten-free diet (p=0.041). In contrast, the DQA1*0501 allele did not have a significant association with the severity of CD. CONCLUSIONS: Our results demonstrate a gene dose effect of the DQB1*0201 allele on the clinical heterogeneity of CD and on the rate of recovery from villous atrophy in patients on a gluten-free diet.     

Sequence analysis of the diabetes-protective human leukocyte antigen-DQB1*0602 allele in unaffected, islet cell antibody-positive first degree relatives and in rare patients with type 1 diabetes.

The human leukocyte antigen (HLA)-DQA1*0102/DQB1*0602/DRB1*1501 (DR2) haplotype confers strong protection from type 1 diabetes. Growing evidence suggests that such protection may be mostly encoded by the DQB1*0602 allele, and we reported that even first degree relatives with islet cell antibodies (ICA) have an extremely low diabetes risk if they carry DQB1*0602. Recently, novel variants of the DQB1*0602 and *0603 alleles were reported in four patients with type 1 diabetes originally typed as DQB1*0602 with conventional techniques. One inference from this observation is that DQB1*0602 may confer absolute protection and may never occur in type 1 diabetes. By this hypothesis, all patients typed as DQB1*0602 positive with conventional techniques should carry one of the above diabetes-permissive variants instead of the protective DQB1*0602. Such variants could also occur in ICA/DQB1*0602-positive relatives, with the implication that their diabetes risk could be significantly higher than previously estimated. We therefore sequenced the DQB1*0602 and DQA1*0102 alleles in all ICA/DQB1*0602-positive relatives (n = 8) previously described and in six rare patients with type 1 diabetes and DQB1*0602. We found that all relatives and patients carry the known DQB1*0602 and DQA1*0102 sequences, and none of them has the mtDNA A3243G mutation associated with late-onset diabetes in ICA-positive individuals. These findings suggest that diabetes-permissive DQB1*0602/3 variants may be very rare. Thus, although the protective effect associated with DQB1*0602 is extremely powerful, it is not absolute. Nonetheless, the development of diabetes in individuals with DQB1*0602 remains extremely unlikely, even in the presence of ICA, as confirmed by our further evaluation of ICA/DQB1*0602-positive relatives, none of whom has yet developed diabetes.     

Population-based genetic screening for the estimation of Type 1 diabetes mellitus risk in Finland: selective genotyping of markers in the HLA-DQB1, HLA-DQA1 and HLA-DRB1 loci.

AIMS: To improve sensitivity and specificity of the diabetes risk assessment of the population-based genetic screening used in the Finnish Diabetes Prediction and Prevention (DIPP) trial. METHODS: One thousand consecutive newborns enrolled in the DIPP were compared with 316 samples from children with Type 1 diabetes mellitus. A modification of the previously described technique based on hybridization of relevant PCR products with five lanthanide-labelled probes detected by time-resolved fluorometry (TRF) was used. A new probe was designed and allowed discrimination between DQB1*0602 and 0603 alleles, in addition to DQB1*02, *0301 or *0302, each of which required specific probes. A new, added screening strategy was developed for individuals carrying low-risk genotypes through specific typing of DQA1 *05 and *0201 alleles in DQB1*02 positive, and DRB1 typing for DR4 subtypes in DQB1*0302 positive subjects, with a new specifically designed high-resolution TRF-based DR4 subtyping technique. RESULTS: This two-step screening approach enhanced the sensitivity of the detection of genetic risk for Type 1 diabetes mellitus in this cohort up to 85.4%. In the general population cohort, 24.4% were identified for prospective follow-up, 2.6% of these are expected to develop Type 1 diabetes mellitus before the age of 15 years. Exclusive typing for HLA-DQB1 locus as an alternative screening strategy had sensitivities of 26.3-77.2% with general population cohorts of 2.3-23.1% identified for follow-up. CONCLUSIONS: The described strategy for genetic prediction of Type 1 diabetes mellitus relies on the convenient genotyping procedure and could be applied in large scale screening projects such as DIPP.     

HLA DRB1/DQA1/DQB1 haplotype determines thyroid autoimmunity in patients with insulin-dependent diabetes mellitus

OBJECTIVE  Thyroid autoimmunity is frequently associated with insulin-dependent diabetes mellitus (IDDM). The genetic factors which contribute to thyroid autoimmunity and IDDM have been described but vary between different races. We have therefore investigated the effect of class II HLA genes at both loci and the HLA haplotypes on the presence of autoimmunity in patients with IDDM in Taiwan.
SUBJECTS AND MEASUREMENTS  Eighty-three patients with IDDM and 105 unrelated normal controls were recruited for the measurement of thyroid autoantibodies and for genotyping of HLA DRB1, DQA1 and DQB1 by polymerase chain reaction-based DNA typing techniques.
RESULTS  Among 83 patients with IDDM, 23 (27.7%) were positive for antithyroid autoantibodies. Compared to those without thyroid autoimmunity, there was a female preponderance for IDDM with thyroid autoimmunity (female: male, 3:20 vs 29:31). Among the DR specificities, DR6 was associated with a weak protective effect against thyroid autoimmunity in IDDM patients. Upon detailed analysis of class II HLA haplotypes, the DRB1*0301/DQA1*0501/DQB1*0201 haplotype was found to be associated with an increased risk of IDDM regardless of thyroid autoimmunity, while DRB1*0405/DQA1*0301/DQB1*0401 was significantly increased only in the IDDM patients with thyroid autoimmunity. IDDM individuals with the HLA DRB1*0405/DQA1*0301/DQB1*0302 haplotype were not at risk of thyroid autoimmunity.
CONCLUSIONS  Our data indicated that there was a generalized genetic factor within or associated with the DRB1*0301/DQA1*0501/DQB1*0201 haplotype, and a more restricted effect with the DRB1*0405/DQA1*0301/DQB1*0401 haplotype which led to thyroid autoimmunity in patients with insulin-dependent diabetes mellitus.     

Contribution of selective HLA-DRB1/DQB1 alleles and haplotypes to the genetic susceptibility of type 1 diabetes among Lebanese and Bahraini Arabs

CONTEXT: Human leukocyte antigen (HLA) class II genes contribute to the genetic susceptibility of type 1 diabetes (T1D), and both susceptible and protective alleles were implicated with its pathogenesis, which varies among various ethnic/racial groups. OBJECTIVE: This study investigated the heterogeneity in HLA class II haplotypes distribution among Bahraini and Lebanese T1D patients. DESIGN: This was a cross-sectional retrospective study. SETTING: The study was conducted at primary care private and public health centers. PATIENTS AND OTHER PARTICIPANTS: Subjects comprised 126 T1D patients and 126 healthy controls from Bahrain and 78 Lebanese T1D patients and 111 control subjects. Intervention(s): There were no interventions. RESULTS: Although Lebanese and Bahraini patients share DRB1*030101, DQB1*0201 as susceptible and DRB1*100101 and DQB1*030101 as protective alleles, DRB1*040101 was an additional susceptible allele in Bahraini patients, and DRB1*130701 and DQB1*050101 were additional susceptible and protective alleles in Lebanese, respectively. DRB1*030101-DQB1*0201 was susceptible, whereas DRB1*070101-DQB1*0201 and DRB1*110101-DQB1*030101 were protective haplotypes in Bahraini and Lebanese. DRB1*040101-DQB1*0302 and DRB1*040101-DQB1*050101 displayed different associations: they were protective in Lebanese but susceptible or neutral among Bahrainis. Whereas the frequency of homozygous DRB1*03011-DQB1*0201 was higher in Bahraini and to a lesser extent Lebanese patients, homozygous DRB1*110101-DQB1*030101 was significantly more frequent in Lebanese but not Bahraini controls, whereas DRB1*030101-DQB1*0201/DRB1*040101-DQB1*0201 was the major genotype among Bahraini patients but not Lebanese subjects in whom it was present at very low frequencies. CONCLUSION: In view of these differences between Bahraini and Lebanese, this demonstrates that the contribution of HLA class II to the genetic susceptibility to T1D must be evaluated with regard to specific HLA haplotypes and also ethnic origin and racial background.     

Association between human leukocytes antigen alleles and chronic hepatitis C virus infection in the Korean population.

BACKGROUND/AIM: Recent data have shown that the clinical outcome of hepatitis C virus (HCV) infection may be influenced by the host genetic factor. The aim of this study was to investigate whether particular human leukocytes antigen (HLA) molecules are associated with the susceptibility to HCV infection in the Korean population. METHODS: One hundred and thirty-seven patients with chronic HCV infection and 206 normal individuals were examined for HLA class I and II molecules. RESULTS: In class I antigens, the frequencies of HLA-A3 (relative risk (RR)=3.5, P<0.04), HLA-B35 (RR=2.0, P<0.03), and HLA-B46 (RR=2.5, P<0.02) significantly increased in chronic HCV carriers compared with the controls. The frequencies of DRB1*0803, DQB1*0601 and DQB1*0604 were significantly higher in chronic HCV carriers than in controls (RR=2.5, P<0.005; RR=1.8, P<0.05; RR=1.9, P<0.04, respectively). On the other hand, the frequencies of DRB1*0301, DQA1*0501 and DQB1*0201 were significantly lower in chronic HCV carriers than in normal controls (RR=0.2, P<0.03; RR=0.4, P<0.004; RR=0.5, P<0.02, respectively). The haplotype DRB1*0803-DQB1*0601 significantly increased (RR=2.5, P<0.02) while the DQA1*0501-DQB1*0201 significantly decreased (RR=0.2, P<0.03) in chronic HCV carriers compared with normal controls. In stratification analysis to investigate the interrelationships among the associated alleles, DRB1*0803 and DQB1*0601 were associated with HLA-B46, particularly in patients with chronic HCV carriers. CONCLUSIONS: These results suggest that particular HLA alleles may have an influence on chronic HCV infection as a host genetic factor in the Korean population.     

The presence or absence of a retroviral long terminal repeat influences the genetic risk for type 1 diabetes conferred by human leukocyte antigen DQ haplotypes. Belgian Diabetes Registry

Major genetic susceptibility to type 1 diabetes mellitus maps to the human leukocyte antigen (HLA) region on chromosome 6p. During evolution, endogenous retroviral long terminal repeats (LTR) have been integrated at several sites within this region. We analyzed the presence of a solitary HERV-K LTR in the HLA DQ region (DQ-LTR3) and its linkage to DRB1, DQA1, and DQB1 haplotypes derived from 246 German and Belgian families with a patient suffering from type 1 diabetes mellitus. Segregation analysis of 984 HLA DQA1/B1 haplotypes showed that DQ-LTR3 is linked to distinct DQA1 and DQB1 haplotypes but is absent in others. The presence of DQ-LTR3 on HLA DQB1*0302 haplotypes was preferentially transmitted to patients from heterozygous parents (82%; P < 10(-6)), in contrast to only 2 of 7 DQB1*0302 haplotypes without DQ-LTR3. Also, the extended HLA DRB1*0401, DQB1*0302 DQ-LTR3-positive haplotypes were preferentially transmitted (84%; P < 10(-6)) compared with 1 of 6 DR-DQ matched DQ-LTR3 negative haplotypes. DQ-LTR3 is missing on most DQB1*0201 haplotypes, and those LTR3 negative haplotypes were also preferentially transmitted to patients (80%; P < 10(-6)), whereas DQB1*0201 DQ-LTR3-positive haplotypes were less often transmitted to patients (36%). Other DQA1/B1 haplotypes did not differ for DQ-LTR3 between transmitted and nontransmitted haplotypes. Thus, the presence of DQLTR3 on HLA DQB1*0302 and its absence on DQB1*0201 haplotypes are independent genetic risk markers for type 1 diabetes.     

Islet cell antibody-positive relatives with human leukocyte antigen DQA1*0102, DQB1*0602: identification by the Diabetes Prevention Trial-type 1

The presence of human leukocyte antigen (HLA) haplotype DQA1*0102, DQB1*0602 is associated with protection from type 1 diabetes. The Diabetes Prevention Trial-type 1 has identified 100 islet cell antibody (ICA)-positive relatives with this protective haplotype, far exceeding the number of such subjects reported in other studies worldwide. Comparisons between ICA+ relatives with and without DQB1*0602 demonstrated no differences in gender or age; however, among racial groups, African-American ICA+ relatives were more likely to carry this haplotype than others. The ICA+ DQB1*0602 individuals were less likely to have additional risk factors for diabetes [insulin autoantibody (IAA) positive or low first phase insulin release (FPIR)] than ICA+ relatives without DQB1*0602. However, 29% of the ICA+ DQB1*0602 relatives did have IAA or low FPIR. Although half of the ICA+ DQB1*0602 relatives had a high risk second haplotype, this was not associated with the additional risk factors for diabetes. Hispanic ICA+ individuals with DQB1*0602 were more likely to be IAA positive or to have low FPIR than other racial groups. In conclusion, the presence of ICA in the relatives described here suggests that whatever the mechanism that protects DQB1*0602 individuals from diabetes, it is likely to occur after the diabetes disease process has begun. In addition, there may be different effects of DQB1*0602 between ethnic groups.     

Frequency of DRB1-DQB1 two-locus haplotypes in tuberculosis: preliminary report

Analysis of correlation between tuberculosis (TB) and human leukocyte antigen (HLA) in populations from Asia and Latin America has shown conflicting results. The aim of this study was to evaluate the frequency of HLA-DRB1-DQB1 two-locus haplotypes of 61 TB patients and 125 healthy volunteers in the same ethnic group in Poland. DRB1 and DQB1 alleles were determined by PCR-SSP "low-resolution" and "high-resolution" methods. Our study showed that DRB1*1601 and DQB1*0502 alleles were more frequent, whereas DQB1*0201 was rarer in TB than in controls. DRB1*16-DQB1*05, DRB1*04-DQB1*03 and DRB1*1601-DQB1*0502 haplotype were more common, and DRB1*11-DQB1*03 less frequent in TB in comparison to controls. Positive linkage disequilibrium (LD) for DRB1*01-DQB1*05, DRB1*03-DQB1*02, DRB1*11-DQB1*03, DRB1*13-DQB1*06 and DRB1*15-DQB1*06 was found in controls. A trend towards the positive LD for DRB1*01-DQB1*05, DRB1*03-DQB1*02, DRB1*11-DQB1*03, DRB1*15-DQB1*06 and DRB1*16-DQB1*05 was shown in TB. The trend towards the positive LD for DRB1*16-DQB1*05 haplotype in TB patients was not observed in the control group. It seems likely that the presence of DRB1*1601, DQB1*0502 alleles and DRB1*1601-DQB1*0502, DRB1*04-DQB1*03, DRB1*14-DQB1*05 haplotypes may be related to a higher risk of developing TB, whereas low frequency of DQB1*0201 and DRB1*11-DQB1*03 haplotype may be linked to the resistance to TB.     

Gene dose effect of the DQB1*0201 allele contributes to severity of coeliac disease

Objective. Coeliac disease (CD) susceptibility has been shown to be associated with the HLA alleles DQA1*0501 and DQB1*0201. This HLA-associated risk has been estimated to account for 29–40% of the genetic component of CD. Conflicting data have been published on the gene dose effect of these HLA alleles on the risk and severity of CD. In this study the aim was to investigate the association between the number of HLA risk alleles and the severity of CD. Material and methods. Fifty-four Finnish CD families, including 144 CD patients mainly diagnosed in adulthood (94.4%), were enrolled in the study. The association between the number of DQA1*0501 and DQB1*0201 alleles and villous atrophy, symptoms and laboratory parameters at the time of diagnosis, and the association with villous atrophy after one year of treatment on a gluten-free diet were studied. Results. The homozygosity for the DQB1*0201 allele was associated with a more severe form of CD assessed by more severe villous atrophy (p=0.011), younger age (p=0.036), more severe diarrhoea (p=0.048) and a lower level of blood haemoglobin at the time of diagnosis (p=0.010). Furthermore, the homozygosity for the DQB1*0201 allele was associated with a slower recovery of villous atrophy after a gluten-free diet (p=0.041). In contrast, the DQA1*0501 allele did not have a significant association with the severity of CD. Conclusions. Our results demonstrate a gene dose effect of the DQB1*0201 allele on the clinical heterogeneity of CD and on the rate of recovery from villous atrophy in patients on a gluten-free diet.     

HLA-DQB1*0201/0302 is associated with severe retinopathy in patients with IDDM

Summary Some insulin-dependent diabetic (IDDM) patients develop severe forms of retinopathy. Putative risk factors such as hypertension, poor metabolic control, nephropathy and growth hormone levels do not fully explain the progress of retinopathy in these patients. It has been discussed whether there is a genetic marker, since some diabetic patients without any known predisposing risk factors develop severe retinopathy and others do not. In the present study, HLA-DR and DQ were compared in two patient groups with IDDM. One group consisted of patients with early-onset diabetes, with severe non-proliferative or proliferative retinopathy; the other group had no or only mild signs of retinopathy. High resolution HLA typing was carried out by polymerase chain reaction (PCR) and hybridization with allele specific probes. Alleles on the DR3-DQ2 haplotype, DRB1^*0301, DQA1*0501 and DQB1^*0201, were more frequent in patients with severe retinopathy. A difference was seen when combining certain alleles in the genotypes of DQA1*03/0501 (p > 0.05) and DQB1^*0201/0302 (p < 0.01). The findings of the present study suggest that DQB1^*0201/0302 is the strongest genetic marker for severe retinopathy and DRB1*0301/0401 only has a secondary influence when combined with this genotype. It seems as if IDDM patients who are positive for the genotype DR3-DQ2/DR4-DQ8 (DRB1^*0301-DQA1*0501-DQB1^*0201/DRB1*0401 -DQA1^*03-DQB1*0302) are at greater risk of developing severe retinopathy. [Diabetologia (1996) 39: 1313–1317] Received: 15 February 1996 and in revised form: 24 April 1996     

Association of HLA-Class II and IgE Serum Levels in Pediatric Asthma

Background: Pediatric bronchial asthma is associated with considerable morbidity. The study was carried out to examine the association of Human Leukocyte Antigen (HLA)- Class II with the disease as we found no similar study on Asian Indian population. Objective: To define the HLA-Class II antigens in Asian Indian pediatric patients with asthma. Methods: A total of 103 children with asthma and 152 controls were analysed for HLA Class II (DRB1, DQB1and DPB1) by PCR-SSP (Sequence Specific Primers) method. Total serum IgE levels were determined by ELISA assay. Results: A positive family history was recorded in 59 patients (57%) and 13 (8.5%) of healthy controls. Serum IgE levels were more than normal range in 72% of the patients and 33% of healthy subjects with mean values of 4877 and 627 IU/ml, respectively. DRB1*04 and DQB1*03 showed significant positive relations while DRB1*15 showed a negative association with asthma. DQB1*02 was more common in healthy individuals but was not statistically significant. Conclusions: A positive association of the DR4/DQB1*03 and a negative association of DRB1*15 was seen with extrinsic bronchial asthma. However, more studies are required on larger populations to confirm the association of HLA Class II alleles in Indians before a particular allele can be labeled as being protective or causative for asthma.     

Linkage disequilibrium between HLA class II region and autoimmune hepatitis in pediatric patients

BACKGROUND/AIMS: Susceptibility HLA class II alleles associated with autoimmune hepatitis (AIH) were only described in case-control studies. METHODS: The transmission/disequilibrium test was used in 50 simplex families with AIH, to determine if affected offspring received the disease-associated allele more frequently than its alternate. HLA-DRB1 and DQB1 allele genotyping and autoimmune regulator (AIRE) polymorphisms located in exons 6, 8 and 10 were investigated by PCR-based methods. RESULTS: HLA-DRB1*03 allele was significantly transmitted from heterozygous parent to affected offspring (81.5%) with type 1 AIH compared to random expected frequency (50.0%; P=0.004) or to unaffected offspring (42.8%; P=0.03). HLA-DRB1*1301 allele showed an excess transmission to affected children (100%) than expected frequency (P<0.0001) or unaffected offspring (P=0.001). The transmission of DQB1*201 or DQB1*0603 alleles showed significant deviation in patients compared to random frequencies: (84.8%; P<0.0001 for DQB1*0201 or 100%; P<0.0001 for DQB1*0603). HLA-DQB1*0201 showed a strong association with type 2 AIH in children (100.0%, P=0.0005). CONCLUSIONS: HLA-DRB1 gene is the major genetic determinant in HLA class II region for children with type 1 AIH. Type 2 AIH is associated with the HLA-DQB1gene. Finally, AIRE gene abnormality does not contribute to the development of isolated AIH.     

Genetic screening for individuals at high risk for type 1 diabetes in the general population using HLA Class II alleles as disease markers. A comparison between three European populations with variable rates of disease incidence

BACKGROUND: To develop screening strategies for identification of individuals at increased genetic risk for type 1 diabetes in three populations with variable disease incidence rates and distinct ethnic origin. METHODS: A stepwise HLA DQB1-DQA1-DRB1-based screening approach was evaluated. Patients with childhood-onset type 1 diabetes were recruited from Finland (n = 1739), Hungary (n = 149), and Greece (n = 119). Consecutive newborns (2568 from Finland and 1047 from Greece) or healthy schoolchildren (n = 177 from Hungary) served as controls. RESULTS: The DQB1*02/0302 genotype conferred the highest disease risk in all populations. The DQB1*02/y (y not equal DQB1*0301,*0302,*0602,*0603, *0604) genotypes were more common and conferred a higher disease risk in the Greek population (OR 4.9) compared to the Finns (OR 1.2). DQB1*0302/x (x not equal DQB1*02, *0301, *0602, *0603, *0604) genotypes were, in contrast, more prevalent among Finnish cases (32.7%) as compared to Hungarians (18.1%) or Greeks (13.5%). The protective DQB1*0602 or *0603 positive genotypes were most common in the Finns, while DQB1*0301 was more common in Hungarians and Greeks. In all groups, DQA1 and DRB1*04 typing considerably increased the sensitivity of the DQB1-based screening. The different high-risk genotype combinations present in about 10% of the background population had a diagnostic sensitivity of 60% in Finland and 80% in Hungary and Greece. CONCLUSIONS: HLA DR-DQ-based screening is a feasible tool for the identification of individuals at increased genetic risk for type 1 diabetes in populations with diverse genetic background. The risk markers should, however, be individually selected for the target population since the screening efficiency of various markers is highly dependent on the ethnic group studied.     

Contrasting cellular and humoral autoimmunity associated with latent autoimmune diabetes in adults

OBJECTIVE: Diabetes is clinically classified into two types: type 1 (T1D) and type 2 diabetes (T2D). Nevertheless, intermediate forms of diabetes are frequent and difficult to recognize and manage appropriately. In this study, we investigated whether patients with intermediate form of diabetes, here called unclassified diabetes (UD), have beta-cell autoimmune markers. RESEARCH DESIGN AND METHODS: beta-cell autoimmune markers (beta-cell autoantibodies (aAb), peripheral blood mononuclear cells (PBMC) responsive to five islet proteins, cytokine secretion, and human leukocyte antigen (HLA)-DQB1 genotypes) were analyzed in 50 UD patients, 23 age- and HLA-matched normal control subjects, and 23 classic T2D patients. RESULTS: We observed that 16 out of 50 (32%) UD patients demonstrated responsive PBMCs, as opposed to 1 out of 23 (5%) age- and HLA-matched normal control subjects, and 0 out of 23 classic T2D patients. Overall, 29 (58%) UD patients had at least one marker of beta-cell autoimmunity (beta-cell aAb and/or PBMC autoreactivity), in association with high-risk HLA genotypes DQB1*0201 and/or DQB1*0302. Moreover, the 13 (26%) UD patients who had beta-cell aAb were not the same as those with PBMC autoreactivity, except for one patient. Patients with PBMC autoreactivity were older at the onset of the disease and had a better residual beta-cell function than those with beta-cell aAb. CONCLUSIONS: Our data confirm that T-cell autoimmunity can be detected in latent autoimmune diabetes in adults patients. We show an inverse correlation between humoral and cellular beta-cell autoimmunities. Possible protective cellular responses in the patients with beta-cell PBMC autoreactivity could have potential therapeutic implications.     

HLA-DQ等位基因与哮喘相关性研究

目的探讨在中国汉族哮喘家系中,HLA-DQ基因与哮喘的相关性。方法对98例哮喘家系成员,用PCR-序列特异性引物(PCR-SSP)技术对HLA-DQA1和B1进行基因分型,并与正常对照进行比较。结果发现DQA1*0101和DQA1*0601等位基因频率在哮喘患者组(40.0%,45.0%)较正常对照组(16.4%,13.4%)显著升高(χ2=6.1860,P<0.05,RR=3.39;χ2=11.6090,P<0.01,RR=5.27);DQB1*0303和DQB1*0601等位基因频率在哮喘患者组(55.0%,47.5%)较正常对照组(13.7%,13.7%)显著升高(χ2=15.7400,P<0.01,RR=7.68;χ2=10.9300,P<0.01,RR=5.69)。同时发现HLA-DQB1*0201等位基因频率在对屋尘螨抗原特异性IgE反应哮喘家系成员(39.4%)较家系中非特应症者（12.0％）显著高频表达(t=2.3825,P<0.05)。结论HLA-DQA1*0101,*0601和DQB1*0303,*0601是哮喘遗传易感等位基因;HLA-DQB1*0201限定对屋尘螨抗原特异性IgE反应。