Is leptin receptor gene (Gln223Arg) polymorphism associated with disease susceptibility and severity in patients of primary knee osteoarthritis?

Aim of the workA significant role of Leptin receptor (LEPR) is documented in inflammation, body weight homeostasis and maintenance of cartilage. This study was conducted to detect the existence of genetic association between Knee osteoarthritis (KOA) susceptibility and severity; and LEPR (Gln223Arg) single nucleotide polymorphism (SNP).Patients and methods73 primary KOA patients and 73 matched healthy controls were studied. Kellgren Laurence (K/L) radiographic grading system, Western Ontario and McMaster Universities Arthritis Index (WOMAC) score and Visual Analogue Scale (VAS) were used to assess the severity of KOA. LEPR Gln223Arg SNP (rs1137101) was genotyped in KOA patients and controls using polymerase chain reaction-restriction fragment length polymorphism (PCR –RFLP) technique and verified by direct DNA sequencing.ResultsIn the current study, a significant genetic association was found between KOA patients carrying the AA genotype of LEPR and the extent of radiological severity (p < 0.044). In addition, a significant difference was detected within the patients between Body Mass Index (BMI) and the SNP. Patients carrying the wild type (GG) genotype showed lower body mass index (BMI) in comparison to patients carrying the heterozygous (AG) genotype and the mutant (AA) genotype (p < 0.032). However, no direct genetic association was detected between the SNP and KOA.ConclusionLeptin receptor gene (Gln223Arg) SNP might be associated with severity of KOA. There is a significant genetic association between the SNP and BMI hence, LEPR SNP might be indirectly associated with the incidence of KOA. Furthermore, the SNP is not directly associated with KOA susceptibility in the Egyptian population.     

Association of Gln222Arg polymorphism in the deoxyribonuclease I (DNase I) gene with myocardial infarction in Japanese patients.

AIMS: We have recently reported that serum deoxyribonuclease I (DNase I) activity, which may be involved in apoptosis, increases abruptly in the early phase of acute myocardial infarction (MI) [Kawai Y, Yoshida M, Arakawa K, Kumamoto T, Morikawa N, Masamura K, Tada H, Ito S, Hoshizaki H, Oshima S, Taniguchi K, Terasawa H, Miyamori I, Kishi K, Yasuda T. Diagnostic use of serum deoxyribonuclease I activity as a novel early-phase marker in acute myocardial infarction. Circulation 2004;109:2398-2400]. Death of vascular smooth muscle cells, in part because of apoptosis, is postulated to heighten susceptibility to disruption of vulnerable plaque, resulting in onset of MI. The present study evaluated the possibility that Gln222Arg polymorphism of the DNase I gene may be one of the factors involved in predisposition to MI. METHODS AND RESULTS: We assessed 611 Japanese patients: 311 with MI and 300 with stable angina pectoris (AP). Three common phenotypes determined by two common codominant alleles, DNASE1*1 and *2, whose corresponding gene products exhibit different properties, were found in these patient groups. The prevalence of DNASE1*2 was significantly higher in patients with MI than in those with AP (0.543 vs. 0.428, P < 0.001), being confirmed by phenotyping of the second study population. Multiple logistic regression analysis showed that the odds ratio of DNASE1*2 was 1.51 [95% confidence interval (CI) 1.04-2.18]. The association of the DNASE1*2 allele with MI was statistically significant, being independent of other conventional risk factors. CONCLUSION: Our data demonstrate that Gln222Arg polymorphism in the DNase I gene is associated with MI in the Japanese patients.     

The association between RAD18 Arg302Gln polymorphism and the risk of human non-small-cell lung cancer

Purpose The repair enzyme RAD18 plays a key role in the post-replication repair process in various organisms from yeast to human, and the molecular function of the RAD18 protein has been elucidated. Single nucleotide polymorphism (SNP) of arginine (Arg, CGA) or glutamine (Gln, CAA) at codon 302 is known on RAD18; however, the association between the SNP and the risk of any human cancers including non-small-cell lung cancer (NSCLC) has not been reported. We therefore investigated the relationship between the polymorphism and the development and progression of human NSCLC. Methods The study population included 159 patients with NSCLC and 200 healthy controls. The SNP was genotyped by polymerase chain reaction with the confronting two-pair primer (PCR-CTPP) assay. Genotype frequencies were compared between patients and controls, and the association of genotypes with clinicopathological parameters was also studied. Results The Gln/Gln genotype was significantly more frequent in NSCLC patients (20.7%) than in healthy controls (11.5%)(P = 0.003). The increased risk was detected in NSCLC patients with the Gln/Gln genotype [Odds ratio (OR) = 2.63, 95% confidence interval (CI)=1.38–4.98]. As to the relationship of the SNP with clinicopathological parameters of NSCLC, significantly higher risks were detected in lung squamous cell carcinoma (LSC) (OR = 4.40, 95% CI = 1.60–12.1). Conclusions Our results suggested that Gln/Gln genotype of the RAD18 SNP has the increased risk of NSCLC, especially of LSC. This is the first report to provide evidence for an association between the RAD18 Arg302Gln polymorphism and human NSCLC risk.     

Paraoxonase 1 192 Gln/Arg gene polymorphism and cerebrovascular disease: interaction with type 2 diabetes.

Paraoxonase 1 (PON1) is an HDL-associated enzyme which protects HDL and LDL particles from lipid peroxidation. Its enzymatic serum activity varies 10-40-fold between individuals, and its biallelic gene polymorphism at codon 192 (glutamine-->arginine, Gln/Arg) has been associated with coronary artery disease in diabetic patients. To evaluate the role of this PON1 gene polymorphism in cerebrovascular disease, we determined the PON1 192 genotype in 149 patients with hemodynamically relevant extracranial artery stenosis and in 241 controls. The PON1 192 Gln/Arg genotype was determined using polymerase chain reaction followed by Alw I digestion and polyacrylamide gel electrophoresis. Among all subjects, there was no association between the PON1 192 Gln/Arg genotype and cerebrovascular disease (Odds ratio for Arg/Arg and Gln/Arg vs Gln/Gln 0.99, 95%-CI 0.70-1.39). In contrast, in the subgroup of type 2 diabetic patients the PON1 192 Arg allele conferred about twice the risk of cerebrovascular stenosis compared to those homozygous for the Gln allele (Odds ratio 2.00, 95%-CI 0.92-4.38). Our data indicate that in the general population the PON1 192 Gln/Arg gene polymorphism cannot be regarded as a major risk marker for cerebrovascular disease. The observed interaction with type 2 diabetes, however, is supporting the hypothesis that the effect of the PON1 192 Arg allele on atherosclerosis is modulated by other risk factors like diabetes.     

Efficiency of the DNA repair and polymorphisms of the XRCC1, XRCC3 and XRCC4 DNA repair genes in systemic lupus erythematosus

Impaired DNA repair efficiency in systemic lupus erythematosus (SLE) patients has been reported in some studies, mainly regarding the repair of oxidative damage, but little is known about repair kinetics towards primarily single-stranded DNA breaks. In the present study, we aimed to investigate: (a) the efficiency of SLE peripheral blood leucocytes in repairing DNA damage induced by ionizing radiation and (b) the association of DNA repair gene (XRCC1 Arg399Gln, XRCC3 Thr241Met and XRCC4 Ile401Thr) polymorphisms in SLE patients, considering the whole group, or stratified sub-groups according to clinical and laboratory features. A total of 163 SLE patients and 125 healthy controls were studied. The kinetics of DNA strand break repair was evaluated by the comet assay, and genotyping for DNA repair genes was performed by PCR-RFLP. Compared with controls, SLE leucocytes exhibited decreased efficiency of DNA repair evaluated at 30 min following irradiation. A significant association with DNA repair gene polymorphisms was not observed for the whole group of SLE patients; however, the XRCC1Arg399Gln polymorphism was associated with the presence of anti-dsDNA antibody. The concomitance of two DNA repair polymorphic sites was associated with the presence of neuropsychiatric manifestations and antiphospholipid antibody syndrome. Taken together, these results indicated that SLE leucocytes repair less efficiently the radiation-induced DNA damage, and DNA repair polymorphic sites may predispose to the development of particular clinical and laboratory features.     

β2-肾上腺素能受体多态性/单倍型与支气管哮喘表型的相关性

目的 研究β2-肾上腺素能受体基因的多态性/单倍型与支气管舒张剂的反应性及血清免疫球蛋白E的负对数(lgIgE)间的关系.方法 2006年2月至2007年2月采用DNA测序法测定了201例哮喘患者(哮喘组)和276名健康对照者(健康对照组)的β2-AR基因5个位点(-47、-20、46、79、252)的基因型并确定其单倍型.统计学处理采用SPSS 11.5软件.以拟和优度的x2检验计算各位点基因型频率是否符合Hardy-Weinberg平衡.5个位点基因型的频率比较采用卡方检验,位点间的连锁不平衡采用确切概率法,不同基因型及单倍型与定量指标间的比较采用方差分析.如果方差分析有统计学意义,则用LSD方法对各组间的值进行两两比较.结果 哮喘组中Arg16Arg16基因型患者的支气管舒张剂反应性为(13±4)L,与Arg16Gly16基因型[(7±3)L]及G1y16Gly16基因型[(7±3)L]比较差异有统计学意义(F=81.55,P＜0.01);在哮喘组6种单倍型中,单倍型Arg16Gln27/Arg16Gln27的△FEV1最高[(13.4±3.5)L],与其他种单倍型[Gly16Gln27/Gly16Gln27(6.4±0.6)L、Gly16Glu27/Gly16Glu27(7.6±3.1)L、Gly16Gln27/Gly16Glu27(6.9±3.5)L、Gly16Gln27/Arg16Gln27(7.2±3.3)L及Gly16Glu27/Arg16Gln27(7.9±2.7)L]比较差异有统计学意义(F=32.55,P＜0.01);哮喘组中Gln27Gln27基因型患者的血清lgIgE为(2.51±0.33)IU/L,与Gln27Glu27基因型患者的血清lgIgE[(2.30±0.82)IU/L]比较差异有统计学意义(F=3.89,P＜0.05);哮喘组中单倍型Gly16Glu27/Arg16Gln27的血清lglgE最低[(2.13±0.15)IU/L],与其他4种单倍型[Arg16Gln27/Arg16Gln27为(2.56±0.14)IU/L、Gly16Glu27/Gly16Glu27为(2.40±0.16)IU/L、Gly16Gln27/Gly16Glu27为(2.54±1.26)IU/L、Gly16Gln27/Arg16Gln27为(2.48±0.48)IU/L]比较差异有统计学意义(F=3.56,P＜0.01).结论 依据所研究的哮喘表型,无论是β2-AR基因的多态性,还是单倍型均可能影响疾病的表现.     

DNA repair gene XRCC1 and XPD polymorphisms and their association with coronary artery disease risks and micronucleus frequency

Coronary artery disease (CAD) is a multifactorial process that appears to be caused by the interaction of environmental risk factors with multiple predisposing genes. In this study, we investigated the effects of the XPD Lys751Gln and XRCC1 Arg399Gln polymorphisms on the presence and the severity of CAD. We also investigated the presence of DNA damage in the peripheral lymphocytes of patients with CAD by using the micronucleus (MN) test and the effect of XPD Lys751Gln and XRCC1 Arg399Gln polymorphisms on this damage. The study population consisted of 147 patients with angiographically documented CAD and 48 healthy controls. No association between XPD Lys751Gln or XRCC1 Arg399Gln polymorphisms and the presence or the severity of CAD was observed. On the other hand, a significantly higher frequency of MN was observed in CAD patients compared with controls (5.7 ± 1.9 vs 5.0 ± 2.1, respectively, P = 0.018). We found an elevated frequency of MN in CAD patients with the XPD 751Gln allele (Gln/Gln genotype) or the XRCC1 399Gln (Arg/Gln or Gln/Gln genotypes) allele compared with the XPD 751Lys (Lys/Lys genotype) allele or XRCC1 399 Arg (Arg /Arg genotype) allele, respectively. These preliminary results suggest that XPD Lys751Gln and XRCC1 Arg399Gln polymorphisms may not be a significant risk factor for developing CAD. In addition, our results indicate that the MN frequency is associated with presence, but not severity, of CAD and is related to the XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms, suggesting an elevated frequency of MN in CAD patients with the XPD 751Gln or XRCC1 399Gln alleles.     

DNA repair genes polymorphisms in multiple myeloma: no association with XRCC1 (Arg399Gln) polymorphism, but the XRCC4 (VNTR in intron 3 and G-1394T) and XPD (Lys751Gln) polymorphisms is associated with the disease in Turkish patients

OBJECTIVE: This study aims to investigate the association between the polymorphisms in DNA repair genes (XPD, XRCC1, and XRCC4) and clinical parameters in patients with multiple myeloma (MM), their effects on prognosis and their roles in susceptibility to MM. Patients and methods: Sixty patients, diagnosed with MM and 70 individuals as the healthy control group were included in the study. Gene polymorphisms were detected with the polymerase chain reaction and/or polymerase chain reaction-restriction fragment length polymorphism method. When the genotype frequencies of XPD (Llys751Gln) and XRCC1 (Arg399Gln) genes were examined in the patient and control groups, no significant difference was detected, while a significant association was found in XRCC4 (VNTR in intron 3 and G-1394T) polymorphisms. A significant association was found in the MM patients group for AA genotype and event-free survival (EFS) in terms of XPD (751) gene polymorphism (P = 0.047). When VNTR intron 3 polymorphism was compared for genotype frequency, DD genotype was found to be significantly low (P = 0.012) in the patient group, whereas GG and TT genotypes were found to be significantly lower in the patient group for the genotype frequency XRCC4 (G-1394T) polymorphism when compared to the control group (P = 0.015, P = 0.010, respectively). RESULTS: These data provide support for the hypothesis that a common variation in the genes encoding XRCC4 DNA repair proteins may contribute to susceptibility to myeloma. These findings require further validation in independent populations.     

Angiotensin-converting enzyme gene polymorphism in Kuwaiti patients with systemic lupus erythematosus

OBJECTIVE: To investigate the frequency of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism genotypes in patients with systemic lupus erythematosus (SLE), and to study the correlation between I/D polymorphism of the ACE gene and the clinical manifestations of SLE, especially vascular involvement, lupus nephritis and disease severity. METHODS: The frequency of ACE gene I/D polymorphism genotypes was determined in 92 patients with SLE from Kuwait, and compared to that in 100 ethnically matched healthy controls using the polymerase chain reaction. RESULTS: The distribution of ACE I/D polymorphism and allele frequencies in SLE patients was not significantly different from controls. Further analyses of SLE patients showed that there was a significant association between DD genotype and Raynaud's phenomenon (p=0.008, odd ratio=5.4, 95% confidence interval: 1.6-18.6). However, there was no significant association between the ACE genotype and lupus nephritis or disease severity. CONCLUSION: No difference was found between the distribution of the ACE genotype in SLE patients and the general pop-ulation in Kuwait. However, the presence of the DD genotype may confer susceptibility to the development of vascular morbidity.     

系统性红斑狼疮与CD19基因多态性的相关性研究

目的研究CD19基因第4外显子705位点(以下简称CD19基因705位点)多态性在中国南方地区汉族人群中的分布及其与系统性红斑狼疮(SLE)和狼疮肾炎(LN)的相关性。方法103例患者诊断均符合1982年美国风湿病学会修订的SLE分类标准,男13例,女90例,其中62例伴有LN。正常对照组110例,男21例,女89例。全部研究对象均为无血缘关系的中国南方地区汉族人群。应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法,对所有SLE患者和正常对照者进行CD19基因705位点多态性检测。结果CD19基因705位点多态性在中国南方地区汉族人群中普遍存在。SLE患者CD19基因705位点基因型和等位基因频率分布与正常对照组比较差异无统计学意义(P>0.05);CD19基因705位点基因型和等位基因频率分布,按性别分层后,男性和女性SLE患者分别与正常对照组比较及LN患者和正常对照组比较以及伴有LN患者与未伴有LN的SLE患者间比较,差异均无统计学意义(P>0.05)。结论CD19基因705位点多态性与SLE及LN无相关性。     

Beta 2-adrenergic receptor polymorphisms and haplotypes are associated with airways hyperresponsiveness among nonsmoking men

STUDY OBJECTIVE: To investigate the relationship of common single nucleotide polymorphisms (SNPs) of the beta(2)-adrenergic receptor (AR) gene at codons 16 and 27, and the intermediate phenotype of airways hyperresponsiveness. DESIGN: A case-control study in 543 white men (152 case patients and 391 control subjects), who were nested in an ongoing longitudinal cohort. SETTING: Subjects were selected from the Normative Aging Study, an ongoing longitudinal cohort of healthy aging. PARTICIPANTS: Case patients were defined as those having a positive response to methacholine challenge testing. Control subjects were selected among those who did not have a diagnosis of asthma and who had no response to methacholine. RESULTS: There was a trend for an association of the Arg16 SNP genotype with airways hyperresponsiveness (odds ratio, 1.25; 95% confidence interval, 0.96 to 1.64 [in an additive model]). In stratified analyses, the effect of the Arg16 variant was seen mainly among nonsmokers. Smokers had increased risks for airway hyperresponsiveness regardless of genotype at either SNP. Using a program to estimate haplotype frequencies, three common haplotypes were identified. Adjusting for age, baseline FEV(1), serum IgE level, and smoking status, the Gly16/Gln27 haplotype was negatively associated with airways hyperresponsiveness in the full complement of case patients and control subjects (score statistic, - 2.43; p = 0.02). The effect of the beta(2)-AR haplotypes was much stronger among lifelong nonsmokers, among whom the Gly16/Gln27 haplotype remained negatively associated with airways hyperresponsiveness (score statistic, - 3.114; p = 0.002), whereas the Arg16/Gln27 haplotype was positively associated with airways hyperresponsiveness (score statistic, 3.142; p = 0.002). No effects were seen among ever-smokers. CONCLUSIONS: In this cohort of middle-aged to older white men, beta(2)-AR polymorphisms were associated with airways hyperresponsiveness, particularly among lifelong nonsmokers. Our results illustrate an instance in which greater power is obtained by performing haplotype analyses as opposed to single SNP analysis.     

Two single-nucleotide polymorphisms in the 5' and 3' ends of the osteopontin gene contribute to susceptibility to systemic lupus erythematosus

OBJECTIVE: To test the association of osteopontin (OPN) polymorphisms with systemic lupus erythematosus (SLE). METHODS: The coding 5' and 3' flanking regions of the OPN gene were scanned for polymorphisms by denaturing high-performance liquid chromatography. A case-control association study was performed in 394 Italian SLE patients and 479 matched controls. OPN serum levels were determined by enzyme-linked immunosorbent assay in 40 patients and 124 controls, and the mean levels were compared between the different OPN genotypes. RESULTS: Among the 13 detected single-nucleotide polymorphisms (SNPs), alleles -156G (frequency 0.714 versus 0.651; P = 0.006, corrected P [P(corr)] = 0.036) and +1239C (0.377 versus 0.297; P = 0.00094, P(corr) = 0.0056) were significantly increased in the SLE patients compared with the controls. The presence of the associated allele in single or double dose conferred an odds ratio (OR) of 2.35 (95% confidence interval [95% CI] 1.38-4.02) for SNP -156 and an OR of 1.57 (95% CI 1.16-2.13) for SNP +1239. These effects were independent of each other, i.e., not a consequence of linkage disequilibrium between the 2 alleles. The risk associated with a double dose of susceptibility alleles at both SNPs was 3.8-fold higher (95% CI 2.0-7.4) relative to the complete absence of susceptibility alleles. With regard to individual clinical and immunologic features, a significant association was seen between lymphadenopathy and -156 genotypes (overall P = 0.0011, P(corr) = 0.046). A significantly increased OPN serum level was detected in healthy individuals carrying +1239C (P = 0.002), which is indicative of an association between the SLE susceptibility allele and OPN levels. CONCLUSION: These data suggest the independent effect of a promoter (-156) and a 3'-untranslated region (+1239) SNP in SLE susceptibility. We can speculate that these sequence variants (or others in perfect linkage disequilibrium) create a predisposition to high production of OPN, and that this in turn may confer susceptibility to SLE.     

Association study of Toll-like receptor 5 (TLR5) and Toll-like receptor 9 (TLR9) polymorphisms in systemic lupus erythematosus

OBJECTIVE: Toll-like receptors (TLR) play an important role in both adaptive and innate immunity. Variations in TLR genes have been shown to be associated with various infectious and inflammatory diseases. We investigated the association of TLR5 (Arg392Stop, rs5744168) and TLR9 (-1237T-->C, rs5743836) single nucleotide polymorphisms (SNP) with systemic lupus erythematosus (SLE) in Caucasian American subjects. METHODS: We performed a case-control association study and genotyped 409 Caucasian women with SLE and 509 Caucasian healthy female controls using TaqMan allelic discrimination (rs5744168) or polymerase chain reaction-restriction fragment length polymorphism analysis (rs5743836). RESULTS: None of the 2 TLR SNP showed a statistically significant association with SLE risk in our cohort. CONCLUSION: Our results do not indicate a major influence of these putative functional TLR SNP on the susceptibility to (or protection from) SLE.     

FCGR2A基因多态性与系统性红斑狼疮相关性研究

目的 明确FCGR2A基因H131／R131多态性在中国人群中的分布，探讨该位点是否与系统性红斑狼疮(SLE)的发病有关。方法 应用Taqman MGB方法对340例SLE病人，300例患者父母和183名正常人的H131／R131多态性位点进行大规模等位基因分型，病例对照研究应用χ^2检验，家系为基础的传递不平衡检验应用ETDT22软件。结果 病例对照研究提示SLE组和正常组之间的等位基因频率无明显差异(P=0．413)，传递不平衡检验证实该位点在中国人群SLE家系中无优势传递(P=0．6049)。结论 在中国汉族人群中FCGR2A H131／R131多态性位点与SLE的发病不存在相关性。     

Anti-DNase I antibodies in systemic lupus erythematosus: diagnostic value and share in the enzyme inhibition

Diagnostic accuracy of anti-DNase I antibodies measurement in a differentiation between SLE and other autoimmune rheumatic diseases was evaluated. The share of anti-DNase I and actin in the DNase I activity decrease in SLE was established. Serum samples were obtained from 54 patients with verified SLE, 52 control patients with other autoimmune rheumatic diseases, and 44 healthy persons. Anti-DNase I concentrations were measured by ELISA. Free and actin inhibited DNase I activities were evaluated in the fresh serum samples. The appraisal of antibodies and actin effects on DNase I activity was made using multiple regression. Anti-DNase I antibodies were positive in 35 SLE and 8 control patients, without significant difference between the mean antibody concentrations. Sensitivity of this test was 64.81 %, and specificity—84.62 %. Mean free DNase I activity in SLE was somewhat lower than in the control group as a result of augmented frequency of extremely low enzyme activities. On the contrary, after the exclusion of the latter cases we have revealed elevated mean free DNase I activity in the other SLE patients comparing to the similar control subgroup. Unlike the controls, low serum DNase I activity in SLE arose not only from actin and antibody action, but also, in half of the cases, from unidentified factor, related to active SLE. The accuracy of the anti-DNase I antibodies measurement is approximate to the present reference standard of SLE diagnostics. We first demonstrated that neither antibodies nor actin caused DNase I activity decrease in SLE.     

The human paraoxonase Gln-Argl92 (Q/R) polymorphism in turkish patients with coronary artery disease

It has been suggested that a Q/R (Glnl92Arg) polymorphism of paraoxonase (PON) might be associated with the predisposition to coronary artery disease (CAD). Therefore, we studied the human paraoxonase gene (PON1) polymorphism in Turkish patients with CAD by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). This polymorphism was determined in 96 CAD patients and in 105 control subjects. The frequencies of the QQ, QR, and RR genotypes were found as 36.5, 52.0, and 11.5% in CAD patients and 48.6, 41.0, and 10.4% in control subjects, respectively. The QR genotype was the most common in the patient group, whereas the QQ genotype was more frequent in individuals without CAD. Frequency of the R allele was higher among CAD patients compared to controls (38.5% versus 31%). However, neither the genotype nor the allele distribution of the Gln92Arg polymorphism of PON1 was statistically significantly different between the two groups (P>0.05). Although both systolic and diastolic blood pressure levels were slightly higher in patients with the QQ genotype, there was no differences in regard to age, sex, serum triglyceride, total cholesterol or high-density lipoprotein cholesterol among CAD patients with different PONI Gln192Arg genotypes. In summary, our results suggest that no association exists between the Gln192Arg polymorphism of paraoxonase and CAD in Turkish patients.     

Association of PHRF1-IRF7 region polymorphism with clinical manifestations of systemic lupus erythematosus in a Japanese population

Interferon regulatory factor 7 (IRF7) has an essential role in the production of type I interferon. Although recent studies detected association of a single nucleotide polymorphism (SNP) rs4963128 in PHD and ring finger domains 1 (PHRF1)/KIAA1542, located closely to IRF7, and IRF7 rs1131665 (glutamine (Gln) 412 arginine (Arg)) with systemic lupus erythematosus (SLE), causal variants have not been established. In this study, we resequenced exons and introns of IRF7 to screen for all common polymorphisms, and examined whether they were associated with SLE in 416 Japanese patients with SLE and 505 healthy controls. We also tested whether the association of PHRF1 rs4963128 with SLE was replicated in a Japanese population. None of the IRF7 polymorphisms was associated with SLE. PHRF1 rs4963128T was not significantly associated with occurrence of SLE either; however, this allele was significantly increased in SLE with anti-Sm antibodies (6.8%) as compared with healthy controls (3.1%, P?=?0.014, odds ratio [OR] 2.31) and SLE without anti-Sm antibodies (3.3%, P?=0.041, OR 2.12). This allele was also increased in SLE with renal disorder (5.1%) as compared with those without renal disorder (2.4%, P?=?0.047, OR 2.17). These results confirmed recently reported association of PHRF1 rs4963128T with anti-Sm antibody positive SLE in African-American populations, and supported the role of PHRF1-IRF7 region in the genetics of SLE.     

Variants in Intron 4 of PD-1 Gene are Associated with the Susceptibility to SLE in an Iranian Population

Background: Programmed cell death protein 1 (PD-1) is a negative costimulatory molecule with immunomodulatory properties. Recently, PD-1 gene defects have attracted attention in the pathogenesis of SLE. Objective: Here, we assessed the association of PD-1 gene polymorphisms in intron 4 and haplotypes with the susceptibility to SLE. Method: Seventy-six SLE patients and 159 healthy controls were included. We screened the polymorphisms by amplifying the intron 4 of the PD-1 gene with the specific primers followed by sequencing. Results: Two distinct SNPs were identified (rs6705653 and rs41386439) within the intron 4 of the PD-1 gene. The AA genotype of +7499 (G/A) SNP was associated with the higher risk of SLE [OR=3.31, 95% CI (1.25-8.76), p-value=0.045], while A allele was identified as a risk allele [OR=1.75, 95% CI (1.10-2.76), p-value=0.015]. However, no significant association was observed between the allele and the genotype frequencies of +7209 (C/T) polymorphic region of the PD-1 gene and susceptibility to SLE. Haplotype analysis showed the significantly higher presence of H2 haplotype (AC; +7499/+7209) [OR=1.70, 95% CI (1.24-2.33), p-value=0.0012] in SLE patients. Conclusion: To the best of our knowledge, this is the first report of the significant association of PD-1 +7499 (G/A) SNP with the SLE susceptibility and the first detection of both polymorphic loci in a population from Iran. However, more investigations are necessary to confirm these findings.     

Interleukin-23 receptor (IL-23R) gene polymorphisms in acquired aplastic anemia

Acquired aplastic anemia (AA) is a rare disease with a complex pathogenesis. In most cases, T cell-mediated immune destruction of hematopoietic cells results in peripheral blood pancytopenia and bone marrow hypoplasia. A subset of the heterodimeric interleukin-23 receptor gene (IL-23R) is significantly associated with autoimmune-mediated diseases. To examine whether IL-23R single nucleotide polymorphisms (SNPs) might contribute to AA, we selected three IL-23R SNPs with amino acid changes (rs11209026: p.Arg381Gln; rs41313262: p.Val362Ile; and rs11465797: p.Thr175Asn) and compared their frequencies in 279 AA patients and 184 ethnically matched healthy controls. The three SNP prevalences were similar between the AA patients and controls. The Arg381Gln variant, which has a strong protective effect against inflammatory bowel disease, showed no association with AA. Furthermore, IL-23 levels in sera were measured in the AA patients and in controls, and there were no significant differences among them. Our results indicate that these three IL-23R SNPs and serum IL-23 level have no apparent impact on susceptibility to AA.