A population- and family-based study of Canadian families reveals association of HLA DRB1*0103 with colonic involvement in inflammatory bowel disease

The aim of this study was to identify major histocompatibility complex alleles associated with the development and clinical features of inflammatory bowel disease (IBD). Genotyping at the human leukocyte antigen (HLA) DRB1 and DQB1 loci was performed on individuals from 118 Caucasian IBD sibling pair families and on 216 healthy controls. Both population- and family-based association tests were used to analyze data obtained on the entire study population and on clinical subgroups stratified by diagnosis, ethnicity, and disease distribution. HLA DRB1*0103 was significantly associated with IBD (OR = 6.0, p = 0.0001) in a case-control analysis of non-Jewish IBD-affected individuals. This association was apparent among both Crohn's disease (OR = 5.23, p = 0.0007) and ulcerative colitis (OR = 7.9, p = 0.0001) patients and was confirmed in the non-Jewish IBD population by results of family-based association analysis using the transmission disequilibrium test. HLA DQB1*0501 was also associated with IBD (OR = 1.64, p = 0.02) in the non-Jewish population. but statistically significant association of this allele with disease was not detected for Crohn's disease and ulcerative colitis separately. No significant associations were identified among the Jewish patients. In the non-Jewish IBD families, IBD was as strongly associated with the DRB1*0103 DQB1*0501 haplotype as with the DRB1*0103 allele alone. The carrier frequency of the DRB1*0103 allele was found to be 10-fold higher in Crohn's disease patients with pure colonic involvement than in healthy controls (38.5% vs. 3.2%; p = 0.0002). These data demonstrate the association of the HLA DRB1*0103 allele with both Crohn's disease and ulcerative colitis and with large intestine-restricted disease in non-Jewish IBD patients and therefore identify HLA DRB1*0103 as a potentially important contributor to disease susceptibility and to expression of colonic involvement in IBD.     

The incidence of HLA DRB1*0103 in ulcerative colitis patients in north-eastern Poland

BACKGROUND/AIMS: Susceptibility to inflammatory bowel disease is partially genetically determined and the HLA (human leukocyte antigen) alloantigens and genes located in the HLA region have been studied over the course of many years as the candidate genes responsible for ulcerative colitis. Improvements in molecular genotyping have allowed disease association with HLA to be narrowed down to specific subtypes. For class II antigens, increasing phenotype frequency of DRB1*0103, DRB1*1502 is observed and positive correlation to disease susceptibility is proposed. We investigated the incidence of HLA DRB1*0103 in ulcerative colitis patients in North-Eastern Poland and possible association with overall disease susceptibility and clinical course of the disease. METHODOLOGY: 41 patients and 45 healthy control blood donors were included in this study. All subjects were Polish. RESULTS: The incidence of HLA DRB1*0103 was low (2.44%), but was associated with fulminant course of the disease (pancolitis with megacolon toxicum). None of the ethnically matched healthy control blood donors possessed the HLA DRB1*0103 allele (0.00%). CONCLUSIONS: The results gained in the presented study confirm, that in the Polish population HLA DRB1*0103 allele is uncommon and it would not be a useful marker of disease susceptibility.     

A recombined haplotype in the major histocompatibility region contains a cluster of genes conferring high susceptibility to ulcerative colitis in the Spanish population

BACKGROUND: The most consistently described associations in ulcerative colitis (UC) have been with human leukocyte antigen (HLA) class II alleles. Our aim was to look for associations among distinct genetic polymorphisms in the major histocompatibility complex (MHC) that might play a role in determining the susceptibility to UC and especially to the extensive form of the disease. METHODS: A case-control study was performed with a total of 253 patients with UC and 315 healthy controls recruited from a single Spanish center. All the samples and 4 cell lines carrying DRB1*0103 or DRB1*1501 alleles were typed for the HLA-DRB1 class II gene and for a panel of HLA class III markers (D6S273, BAT_2, TNFa, b, c, d, e, IKBL+738, MICA). RESULTS: The frequency of the alleles DRB1*0103, IKBL+738(C) (extending our previous results) and BAT_2-8 (newly typed) was increased in patients compared with controls (P=0.00001, odds ratio [OR]=5.90; P=0.002, OR=2.42; and P=0.0001, OR=3.04, respectively), and these associations were greatest in patients with extensive disease compared with patients with distal disease (P=0.02, OR=2.53; P=0.002, OR=3.06; and P=0.03, OR=2.08, respectively). The allelic combination DRB1*0103/D6S273-5/BAT_2-8/TNFa11b4c1d3e3/IKBL+738(C)/MICA5.1 that includes the telomeric class III markers of the 7.1 ancestral haplotype is highly increased in patients with UC (P=0.0001, OR=10.57), especially in those with the extensive form of the disease (P=0.02, OR=3.41 extensive versus distal). CONCLUSIONS: The above-mentioned pattern, most likely formed by recombination of the telomeric fragment of the MHC 7.1 ancestral haplotype, seems to be the most important genetic determinant of susceptibility to the extensive form of UC in our population.     

HLA-DMA*0103 and HLA-DMB*0104 alleles as novel prognostic factors in rheumatoid arthritis

OBJECTIVE: To evaluate HLA-DM alleles as markers for disease severity in rheumatoid arthritis (RA). METHODS: Two distinct cohorts of patients with RA were oligotyped for HLA-DB1 and HLA-DM genes using PCR amplified genomic DNA with sequence specific oligonucleotide probes. Cohort 1 comprised 199 unselected patients with RA (mean (SD) age 45.5 (13.5) years; disease duration 11.9(8.8) years), whose disease severity was assessed using Larsen score on hand and foot radiographs. Cohort 2 comprised 95 patients with severe RA and 70 patients with benign RA according to the Larsen method. RESULTS: In cohort 1, after stratification according to DRB1 genotypes, patients positive for HLA-DMA*0103 and negative for HLA-DRB1*04 tended to have greater articular damage on hands and wrists (p = 0.07 by Mann-Whitney U test) and reached statistical significance for the Larsen score per year (p = 0.05). This association between HLA-DMA*0103 and articular damage was especially observed in patients with HLA-DRB1*01. Similarly, HLA-DMB*0104 positive patients had higher Larsen score on hands and wrists (p = 0.02). This association was even stronger in DRB1*04 positive patients (p = 0.005). In cohort 2, HLA-DMA*0103 was associated with severe RA in patients negative for HLA-DRB1*04 (OD = 5.4; p = 0.014). HLA-DMB*0104 allele frequency tended to be higher in patients with severe RA but without reaching significance. CONCLUSION: This is the first study evaluating the role of HLA-DM genes in the severity of RA. Our results suggest that HLA-DMA*0103 and HLA-DMB*0104 alleles may represent new genetic markers of RA severity. The HLA-DMA*0103 allele tends to be associated with patients with RA negative for DRB1*04 and could predict a more severe form of disease especially in HLA-DRB1*01 positive patients. The HLA-DMB*0104 allele could have an additive effect in HLA-DRB1*04 patients. Combined determination of HLA-DM and HLA-DRB1 alleles could facilitate identification of patients likely to have a poor disease course.     

溃疡性结肠炎的白细胞介素(IL)-1β、IL-1受体拮抗剂、IL-4基因多态性

目的研究溃疡性结肠炎(UC)病人的白细胞介素(IL)-1β、IL-1受体拮抗剂(IL-1RA)、IL-4基因多态性,并分析其与抗中性粒细胞胞质抗体(ANCA)及临床分型的关系.方法用PCR-限制性片段长度多态性方法和序列特异性引物-PCR方法分别对81例UC病人和114例健康者进行IL-1β和IL-1RA、IL-4基因多态性分析.结果 UC组IL-4 的RP2基因频率明显高于对照组(29.0% 对11.8%,P=0.000 02),而对照组RP1基因频率明显高于UC组(88.2% 对71.0%,P=0.000 02),UC组RP1.2、RP2.2基因型的优势比值分别为2.71 (95%CI, 1.39～5.31),9.04 (95%CI, 1.05～203.29);2组IL-1β、IL-1RA各基因频率比较差异均无显著性 (P＞0.05);ANCA(+)组和ANCA(-)组UC病人IL-4的 RP1、RP2基因频率显著不同,差异有显著性 (P值均<0.05).结论中国汉族UC病人与IL-4内含子3的基因多态性相关联,UC病人IL-4 RP1基因频率明显降低,而RP2基因频率明显增加,与正常人的差异发生在 ANCA(+) UC病人;中国汉族UC病人与IL-1β、IL-1RA基因多态性无关联.     

Pancolitis and genetic markers in the Spanish population.

BACKGROUND: although the etiology of ulcerative colitis disease remains an enigma, the importance of the major histocompatibility complex genes has been described, as in many other autoimmune diseases. AIM: we investigated the contribution of HLA-DRB1, DQA1 and DQB1 genes (HLA region) in patients with pancolitis. METHODS: we studied a total of 89 patients diagnosed as having ulcerative colitis (34 pancolitis and 55 left colitis) and 275 healthy control subjects. Complete information on sex, age, family history, age of onset, localization, complications, surgery and treatment was obtained from all patients. DNA was extracted from peripheral blood leukocytes and all individuals were HLA-DRB1 genotyped. RESULTS AND CONCLUSIONS: there was an association between pancolitis and the presence of DR4-Val86 (p = 0.009; OR = 3.3) and DRB1*0103 (p = 0.02; OR = 5.1) alleles. In patients with left colitis an association with DRB1*1501 (p = 0.03; OR = 1.9) and DRB1*0103 alleles (p = 0.03; OR = 3.8) was observed. We conclude that a strong association between DR4-Val86 and pancolitis exists.     

Susceptibility to severe ulcerative colitis is associated with polymorphism in the central MHC gene IKBL

BACKGROUND & AIMS: IKBL gene lies telomeric of the tumor necrosis factor cluster in the central major histocompatibility complex and carries a structural polymorphism at position +738. In the Spanish white population, we found the IKBL+738(C) allele in haplotypes carrying either HLA-DRB1(*)1501 or -DRB1(*)0103. Because these HLA class II alleles may confer susceptibility to ulcerative colitis, we investigated an association between IKBL+738(C) and this disease. METHODS: DNA-based techniques were used to type individual alleles of HLA-DRB1 and IKBL+738. The frequencies of these alleles were compared among ethnically matched populations comprising 155 patients and 298 controls. RESULTS: IKBL+738(C) allele was exclusively increased in patients with extensive and/or intractable disease. HLA-DRB1(*)0103 was the only HLA-DRB1 allele to be significantly increased in frequency in patients with UC compared with controls. It was found in patients with extensive and distal disease. In the HLA-DRB1(*)0103-negative population, patients with extensive disease still had a significant association with IKBL+738(C). The difference between the 2 groups of patients was statistically significant (13.7% vs. 1.7% in patients with distal disease; odds ratio, 9.25; P = 0.01). CONCLUSIONS: HLA-DRB1(*)0103 is associated with susceptibility to ulcerative colitis, and IKBL+738(C) marks a propensity to extensive and more severe disease.     

Influence of shared epitope-negative HLA-DRB1 alleles on genetic susceptibility to rheumatoid arthritis

OBJECTIVE: Most patients with rheumatoid arthritis (RA) express the shared epitope (SE). It is not known whether SE-negative HLA-DRB1 alleles influence the development of RA. This study examined the influence of SE-negative HLA-DR alleles (DRB1*X) on the development of RA in 3 different French populations. METHODS: HLA-DRB1 alleles were defined by polymerase chain reaction with sequence-specific oligonucleotide hybridization or sequence-specific primers. SE-negative alleles were classified according to the electric charge of their P4 pocket. HLA-DRB1 alleles *0103, *0402, *07, *08, *11 (except *1107), *12, and *13 have a neutral or negative P4 charge and are called DRB1*XP4n. HLA-DRB1*03, *0403, *0406, *0407, *0901, *1107, *14, *15, and *16 have a positive P4 charge and are called DRB1*XP4p. RESULTS: Among the SE-negative subjects, DRB1 genotypes with 1 or 2 DRB1*XP4n alleles were significantly overrepresented in the control subjects compared with the RA patients, whereas DRB1*XP4p/XP4p genotypes were equally represented in the patients and controls. In single-dose SE-positive subjects, SE/XP4n genotypes were equally represented in the patients and controls. However, SE/XP4p genotypes were significantly overrepresented in the RA patients. CONCLUSION: The DRB1*X allele polymorphism influences susceptibility to RA. Alleles that have a neutral or negative electric charge in their P4 pocket (DRB1*XP4n), such as DRB1*0103, *0402, *07, *08, *11 (except *1107), *12, and *13, protect against RA. Alleles that have a positive electric charge in their P4 pocket (DRB1*XP4p), such as DRB1*03, *0403, *0406, *0407, *0901, *1107, *14, *15, and *16, have no influence on the predisposition to RA.     

Associations of HLA‐DRB1 alleles with anti‐citrullinated protein antibody‐positive and anti‐citrullinated protein antibody‐negative rheumatoid arthritis in northern east part of Turkey

Aim: The aim of this study was to investigate the associations between human leukocyte antigen (HLA)‐DRB1 alleles with genetic susceptibility to rheumatoid arthritis (RA) and production of antibodies against cyclic citrullinated peptide (anti‐CCP antibody) and rheumatoid factor (RF) in Turkish RA patients. Methods: We studied 291 RA patients and 253 controls. Genotyping was performed by polymerase chain reaction with sequence‐specific oligonucleotide probes hybridization method. Serum levels of anti‐CCP antibody, IgM‐RF and high sensitive C‐reactive protein titers were measured by commercial kits using immunological methods. Results: We found that HLA‐DRB1*04 and *09 alleles were associated in anti‐CCP+ and anti‐CCP+ RA patients (P < 0.0001 and P < 0.001, respectively), while DRB1*01 and *04 were determined to be higher in RF+ RA patients (P < 0.001 and P < 0.0001, respectively). Moreover, DRB1*11 and DRB1*13 alleles were determined to be lower in RF and anti‐CCP/RF+ RA patients (P < 0.001 for both). HLA‐DRB1*04 was identified as a common responsible allele for susceptibility to the disease in anti‐CCP, RF and anti‐CCP/RF? RA patients (P = 0.0018, P = 0.0004 and P = 0.0023, respectively). HLA‐DRB1*13 allele alone was found to be protective against to anti‐CCP+ and RF? RA (P = 0.0003 and P = 0.006, respectively). On the contrary, there was no protective allele in anti‐CCP/RF? RA as well as anti‐CCP? RA patients. Conclusion: This study indicates that associate and protective HLA‐DRB1 allele distributions are different in autoantibody (anti‐CCP or RF or anti‐CCP/RF)+ RA and autoantibody? RA patients, with exceptions of DRB1*04 and DRB1*13.     

HLA-DRB1 allele distribution and its relation to rheumatoid arthritis in eastern Black Sea Turkish population

Rheumatoid arthritis (RA [MIM 180300]) is a complex, polygenic inflammatory autoimmune disease, resulting from interactions between genetic and environmental factors. Some of the RA-associated HLA-DRB1 alleles have shared epitope, but their distribution varies among different racial/ethnic groups. This study was aimed at investigating the distribution of HLA-DRB1 alleles in patients with RA in eastern Black Sea region of Turkey. DNA samples of 320 patients with RA and 360 healthy controls were studied for the determination of HLA-DRB1 allele distribution using PCR–SSP method. The allele frequencies of HLA-DRB1*01, *04, and *09 were higher in patients with RA compared with the controls (P < 0.005, P < 0.0001, and P < 0.01, respectively). On the other hand, in patients with RA, HLA-DRB1*13 allele was lower than the controls (P < 0.001). Of the HLA-DRB1*04 subgroups, *0401 (40.83% vs. 18.75%, P < 0.001) was the most frequent allele in patients with RA, while DRB1*0402 (30.00% vs. 12.50%, P < 0.005) allele in the controls. HLA-DRB1 allele frequencies in the patients with RA and the controls showed Hardy–Weinberg rule compliance. Results of this study indicate that HLA-DRB1*01, *04, and *09 alleles were associated with RA, and HLA-DRB1*13 was protective allele against RA. Among the subgroups of HLA-DRB1*04, *0401 was detected to be RA associated, while *0402 was being protective. These results have some differences compared with previous reports originating from other regions of Turkey.     

Involvement of transporter associated with antigen processing 2 (TAP2) gene polymorphisms in hepatitis C virus infection

BACKGROUND & AIMS: Transporter associated with antigen processing (TAP) has essential roles in the antigen-presenting systems, translocating antigenic peptides from the cytosol into the endoplasmic reticulum. The aim of this study was to clarify whether TAP polymorphisms are involved in hepatitis C virus (HCV) infection. METHODS: The 145 HCV-infected Japanese patients examined in this study were categorized into two groups: 36 carriers with persistently normal alanine transaminase (ALT) values and 109 patients with chronic liver disease (CLD). TAP2 gene phenotypes were determined by means of polymerase chain reaction-restriction fragment length polymorphism, and their frequencies were compared between the two groups. RESULTS: Frequencies of TAP2*0101, *0102, and *0201 were not different between the two groups. However, TAP2*0103 frequency in carriers with normal ALT levels was significantly higher than that in patients with CLD (44% vs. 16%; P = 0.00064, Pc < 0.005). Although the TAP2*0103 allele was tightly linked with class II DRB1*1302-DQB1*0604 haplotype in this study, the TAP2*0103 frequency in the normal ALT group was also significantly higher than that in the CLD group even in DRB1*1302-DQB1*0604-negative patients (31% vs. 10%; P = 0.0076, Pc < 0.05). CONCLUSIONS: These findings suggest that TAP2*0103 may be closely associated with low serum ALT activity in HCV-infected Japanese patients.     

Genetic heterogeneity within ulcerative colitis determined by an interleukin-1 receptor antagonist gene polymorphism and antineutrophil cytoplasmic antibodies.

BACKGROUND: Although there is strong evidence implicating genetic predisposition in the pathogenesis of the chronic inflammatory bowel diseases, the number and identity of susceptibility genes remain uncertain. Cytokine genes are tentative candidate loci, but data regarding association studies in different populations are conflicting. AIMS: To determine potential associations of interleukin-1 receptor antagonist (IL-1ra), tumour necrosis factor alpha (TNF alpha), and tumour necrosis factor beta (TNF beta) gene polymorphisms with ulcerative colitis or subsets of ulcerative colitis in a Spanish population. METHODS: Genotyping for IL-1ra, TNF alpha and TNF beta gene polymorphisms was performed by the polymerase chain reaction in 95 patients with ulcerative colitis and 74 healthy controls. A variable number of tandem repeats (VNTR) in the IL-1ra gene, and a single base pair polymorphism in the TNF alpha gene promoter region (-308) and in the first intron of the TNF beta gene were analysed. Anti-neutrophil cytoplasmic antibodies (ANCA) were detected using an indirect immunofluorescence assay. RESULTS: There were no significant differences between ulcerative colitis patients and controls in either polymorphism analysed, nor between ulcerative colitis subgroups as a function of the clinical disease pattern. However, when stratified by their ANCA status, perinuclear ANCA (p-ANCA) ulcerative colitis showed an increased frequency of the genotype 1,2 of the IL-1ra gene compared with ANCA-negative ulcerative colitis (52% versus 28%; P = 0.02, Pcorr = 0.1). Furthermore, p-ANCA ulcerative colitis had a statistically significant increase of this genotype compared with cytoplasmic ANCA (c-ANCA)/ANCA-negative ulcerative colitis (52% versus 26.5%; P = 0.01, Pcorr = 0.05). CONCLUSIONS: In the Spanish population studied, the polymorphisms analysed in the IL-1ra, TNF alpha and TNF beta genes are unlikely to be important in the overall susceptibility to ulcerative colitis. However, the combination of a subclinical (p-ANCA) and a genetic (IL-1ra gene) marker identified a distinct ulcerative colitis subgroup (p-ANCA; IL-1ra genotype 1,2). These findings provide further evidence of genetic heterogeneity within ulcerative colitis, and support the concept that ANCA may represent a subclinical marker of genetic heterogeneity.     

Influence of shared epitope–negative HLA–DRB1 alleles on genetic susceptibility to rheumatoid arthritis

Objective

Most patients with rheumatoid arthritis (RA) express the shared epitope (SE). It is not known whether SE‐negative HLA–DRB1 alleles influence the development of RA. This study examined the influence of SE‐negative HLA–DR alleles (DRB1*X) on the development of RA in 3 different French populations.

Methods

HLA–DRB1 alleles were defined by polymerase chain reaction with sequence‐specific oligonucleotide hybridization or sequence‐specific primers. SE‐negative alleles were classified according to the electric charge of their P4 pocket. HLA–DRB1 alleles *0103, *0402, *07, *08, *11 (except *1107), *12, and *13 have a neutral or negative P4 charge and are called DRB1*XP4n. HLA–DRB1*03, *0403, *0406, *0407, *0901, *1107, *14, *15, and *16 have a positive P4 charge and are called DRB1*XP4p.

Results

Among the SE‐negative subjects, DRB1 genotypes with 1 or 2 DRB1*XP4n alleles were significantly overrepresented in the control subjects compared with the RA patients, whereas DRB1*XP4p/XP4p genotypes were equally represented in the patients and controls. In single‐dose SE–positive subjects, SE/XP4n genotypes were equally represented in the patients and controls. However, SE/XP4p genotypes were significantly overrepresented in the RA patients.

Conclusion

The DRB1*X allele polymorphism influences susceptibility to RA. Alleles that have a neutral or negative electric charge in their P4 pocket (DRB1*XP4n), such as DRB1*0103, *0402, *07, *08, *11 (except *1107), *12, and *13, protect against RA. Alleles that have a positive electric charge in their P4 pocket (DRB1*XP4p), such as DRB1*03, *0403, *0406, *0407, *0901, *1107, *14, *15, and *16, have no influence on the predisposition to RA.

     

抗甲状腺药物致白细胞减少易感性与HLA-DRB1基因多态性及ANCA的关联性

目的 研究安徽地区汉族Graves病患者使用抗甲状腺药物(ATD)致白细胞减少的易感性与HLA-DRB1基因多态性及抗中性粒细胞胞浆抗体(ANCA)的相关性.方法 采用聚合酶链反应-序列特异性引物方法(PCR-SSP)检测76例ATD致白细胞减少的Graves病患者、98例ATD治疗后白细胞正常患者和230名健康对照者的等位基因HLA-DRB1* 08032、DRBI* 1501、DRB1*0901的频率.采用间接免疫荧光法(IIF)检测白细胞减少组和白细胞正常组Graves病患者的血清ANCA阳性率.结果 (1)与健康对照组及细胞正常组比较,白细胞减少组患者等位基因DRB1 * 08032、DRB1*1501频率明显增加(OR分别为3.06,1.77,4.03和2.28,均P＜0.05),DRB1* 0901频率明显减低(OR为0.33和0.43,P＜0.05).(2)与甲巯咪唑治疗后白细胞正常组患者比较,甲巯咪唑致白细胞减少组患者血清ANCA阳性率明显增加(x2 =4.878,P＜0.05).(3)与未携带等位基因DRB1*08032和DRB1*1501的患者比较,携带者血清中ANCA阳性率明显增加(x2为5.682,5.429,4.009和4.549,均P＜0.05).结论 等位基因HLA-DRB1*08032、HLA-DRB1*1501可能是安徽地区汉族人ATD致白细胞减少的易感基因;HLA-DRB1*0901可能是其保护基因或抗性基因.免疫反应可能参与了ATD致白细胞减少的发生.免疫反应的发生可能存在遗传易感性.     

Cytokine gene polymorphisms in inflammatory bowel disease.

BACKGROUND: Concordance rates in siblings and twins provide strong evidence that genetic susceptibility is important in the pathogenesis of inflammatory bowel disease. The number and identity of susceptibility genes is largely uncertain. Cytokine genes are attractive candidate loci. AIMS: To study allelic frequencies of polymorphisms of the interleukin-1 receptor antagonist (IL-1RA) gene and the tumour necrosis factor alpha gene in patients with inflammatory bowel disease. SUBJECTS: One hundred and twenty nine North European caucasoid patients with ulcerative colitis, 120 patients with Crohn's disease, and 89 healthy controls. METHODS: Genotyping was performed by polymerase chain reaction. A variable number of tandem repeats (VNTR) in the IL-1RA gene and a single base pair polymorphism in the TNF alpha gene promoter region (TNF-308) were analysed. RESULTS: No significant differences in IL-1RA VNTR allelic frequencies were noted between Crohn's disease (allele 1: 72.6%, allele 2: 24.7%, allele 3: 2.6%), ulcerative colitis (72.6%, 24.3%, 3.1%, respectively), and controls (76.9%, 20.8% and 2.3%). Some 42.4% of patients with ulcerative colitis and 43.4% patients with Crohn's disease were carriers of allele 2, compared with 34.8% healthy subjects. The TNF2 allele was modestly reduced in Crohn's disease (13.2%), compared with healthy subjects (21.3%; p = 0.04), and ulcerative colitis (21.6%). CONCLUSIONS: The associations demonstrated are modest: these polymorphisms are unlikely to be important determinants of overall disease susceptibility.     

The prevalence of human leukocyte antigen (HLA) DR/DQ/DP alleles in Kuwaiti children with oligoarticular juvenile idiopathic arthritis

We have determined the prevalence of human leukocyte antigen (HLA)-DR, DQ and DP alleles in Kuwaiti children with oligoarticular juvenile idiopathic arthritis (OA-JIA) and healthy controls using the PCR-SSP (sequence specific primers) method. The analysis took into account the presence of antinuclear antibodies and chronic anterior uveitis. DRB1*03 (RR 2.20, P<0.001), DRB1*08 (RR 5.280, P<0.026), DQA1*0501 (RR 1.930, P<0.001), DQB1*0304 (RR 7.920, P<0.002), DQB1*0501 (RR 3.080, P<0.007) and DPB1*0101 (RR 8.8, P<0.001) were the main HLA alleles associated with OA-JIA in Kuwaiti Arabs in this study. DRB1*03 was detected in 71% of children with positive ANA, and in 50% of children with anterior uveitis. DQA1 alleles *0501, *0103 and *0105 (P<0.001; 0.029 and 0.024 respectively) were found to be associated with OA-JIA. In contrast, DQA1*0301 and DQA1*0302 alleles appear to be protective in Kuwaiti children (RR 0.153, P<0.001 and RR 0.278, P<0.016 respectively). The DQB1 alleles *0304 and *0501 were associated with OA-JIA (P<0.002 and P<0.007 respectively). In the case of DPB1, only one allele (*0101) was associated with OA-JIA (P<0.001). Most Kuwaiti Arab patients with OA-JIA who carried a DQ or DP susceptibility allele also had an accompanying DRB1*03 or *8 allele.     

Amino Acid Polymorphism at Residue 71 in HLA-DR Beta Chain Plays a Critical Role in Susceptibility to Ulcerative Colitis

The association of ulcerative colitis withdistinct HLA-DRB1 alleles has not been easy toascertain. Recent studies show that among HLA-DR2alleles, DRB1*15 but not DRB1*16, is associated with thedisease. Similarly, in the HLA-DR1 group, only DRB1*0103is increased in ulcerative colitis patients. The aim ofour study was to identify critical DRB1 residues thatmight account for these differences. We typed 121 patients with ulcerative colitis and 275controls using gene amplification and sequence-specificoligonucleotide probing for HLA-DRB1 and DRB3. Weobserved a strong negative association between HLA-DRB1 alleles that encode lysine at position 71 intheir -chain and susceptibility to ulcerativecolitis. Differences in the prevalence among otheralleles differing only in the third hypervariable region suggested a hierarchy of susceptible andprotective class II alleles related to the presence ofan acidic, neutral, or basic amino acid residue atposition 71. These data implicate most strongly theamino acid residues in the third hypervariable regionof the DR chain, especially DR71, in theassociation between ulcerative colitis and HLA. However,this does not exclude the contribution of other parts of the molecule and otherimmunoregulatory genes.     

HLA haplotype analysis in Finnish patients with rheumatoid arthritis

OBJECTIVE: To further characterize the HLA gene products that play an important role in the pathogenesis of rheumatoid arthritis (RA). METHODS: One hundred thirty-four haplotypes from 67 Finnish RA patients and 77 control haplotypes were analyzed for HLA-DRB1 loci, associated alleles of the HLA-DQB1 locus, alleles of the type 2 transporter-associated antigen processing (TAP2) genes, and HLA-B27. In addition, a panel of microsatellite markers within the HLA class I and class III regions was studied. RESULTS: The frequency of HLA-DRB1*04 in the haplotypes of RA patients was found to be 34% (45 of 134) compared with 14% (10 of 72) in control haplotypes (P = 0.004). The frequency of HLA-DRB1*13 was decreased in RA haplotypes (4%, or 5 of 134) in contrast to control haplotypes (24%, or 17 of 72) (P = 0.000031). The decrease in DRB1*13 was not secondary to the increase in DRB1*04, since it was also found among DRB1*04-negative haplotypes (P < 0.001). The DRB1*13-associated DQB1*0604 allele was similarly decreased in RA haplotypes (P = 0.025). The TAP2I allele of I/J dimorphism was increased in RA patients (85%, or 114 of 134) as compared with controls (69%, or 49 of 71) (P = 0.011). Of the tumor necrosis factor (TNF) microsatellite alleles, TNFa6 and TNFb5 were found to be increased in RA haplotypes (for a6 27% versus 5% in controls [P = 0.00043], and for b5 43% versus 26% in controls [P = 0.037]). CONCLUSION: Both protection-associated and susceptibility-associated alleles can be found among HLA class II genes, and the results suggest that loci outside DR/DQ may contribute to the pathogenesis of RA.     

中国内地人群类风湿关节炎与HLA-DRB1共同表位基因关联性的Meta分析

目的探讨中国内地人群类风湿关节炎(RA)与人类白细胞抗原(HLA)-DRB1共同表位(SE)基因的关联情况。方法检索已发表的有关中国内地人群RA和HLA-DRB1的文献,进行汇总分析分析。结果14项研究共纳入1118例RA患者和1301名正常对照,中国内地人群RA的关联基因有HLA-DR4[比值比(OR)=4.05,P<0.0001)]、DRB1*0401(OR=2.66,P=0.004)、DRB1*0404(OR=2.10,P=0.02)、DRB1*0405(OR=3.98,P<0.0001)、DRB1*0410(OR=3.36,P=0.008)、SE(OR=2.75,P<0.00001)。其中DRB1*0405是主要基因亚型。结论汇总分析分析不仅证实了DRB1*0405与中国内地人群RA的关联,而且发现了相对少见基因亚型DRB1*0401、DRB1*0404、DRB1*0410与RA的关联,样本大小对基因关联分析的结论有重要影响。     

The genetic contribution of the TNFa11 microsatellite allele and the TNFb + 252*2 allele in Japanese RA

OBJECTIVES: The contribution of the microsatellite polymorphisms of TNFa and TNFb, and the TNFB + 252 (TNFB) dimorphism to the pathogenesis of rheumatoid arthritis (RA) was studied among Japanese patients. METHODS: The TNFa and TNFb microsatellite polymorphisms, and the TNFB dimorphism were determined in Japanese RA patients and normal subjects using electrophoresis followed by specific PCR amplification. HLA-DRB1*04 typing was carried out by the PCR-SSCP method. RESULTS: The allele frequency of TNFa11 showed a significant increase in RA with DRB1*0405 when compared to that in RA without DRB1*0405 (28.5% Vs 12.9%, respectively, p = 0.022). An association analysis indicated that TNFa11 was not primary, but secondary to the increase in HLA-DRB1*0405, because TNFa11 showed a strong positive association with HLA-DRB1*0405 in Japanese controls. The slight increase in the TNFb4 allele observed in RA with DRB1*0405 (50.0%) may be reflective of the increase in TNFa11 and DRB1*0405. In RA with DRB1*0405, the allele frequency of TNFB*2 significantly increased compared to that of normal controls (75.0% Vs 55.3%, respectively, p = 0.007) and compared to that of RA without DRB1*0405 (45.0%, p = 0.001). No significant positive association of TNFB*2 with HLA-DRB1*0405 or TNFa11 in Japanese controls might suggest that the increase in the TNFB*2 allele might not be secondary to the increase in DRB1*0405, and that TNFB*2 might contribute additively to DRB1*0405-positive RA in Japanese. CONCLUSION: TNFB*2 may contribute additively to Japanese RA with HLA-DRB1*0405, while TNFa11 and TNFb4 are not independent genetic markers of RA among Japanese.