Investigation of the relationship between IL17A,IL17F and ILR1N polymorphisms and COVID-19 severity: The predictive role of IL17A rs2275913 polymorphism in the clinical course of COVID-19

Coronavirus disease 2019 (COVID-19) is an infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the mortality rate of the disease has been relatively under control as of 2022, more than 15 million confirmed COVID-19 cases have been detected in Turkey to date, causing more than 100,000 deaths. The clinical manifestation of the disease varies widely, ranging from asymptomatic to acute respiratory distress syndrome causing death. The immune response mechanisms have an important impact on the fine adjustment between healing and enhanced tissue damage. This study aims to investigate the relationship between the variants of the interleukin 1 receptor antagonist (IL1RN), interleukin 17A (IL17A), and interleukin 17F (IL17F) genes and COVID-19 severity. The study population comprised 202 confirmed COVID-19 cases divided into three groups according to severity. The IL1RN variable number of a tandem repeat (VNTR) polymorphism was genotyped by polymerase chain reaction (PCR), and IL17A rs2275913, IL17F rs763780 and rs2397084 polymorphisms were genotyped by the PCR-based restriction fragment length polymorphism method. Statistical analysis revealed a significant association between IL17A rs2275913 variant and COVID-19 severity. The AA genotype and the A allele of IL17A rs2275913 were found significant in the severe group. Additionally, we found a significant relationship between haplotype frequency distributions and severity of COVID-19 for the IL17F rs763780/rs2397084 (p = 0.044) and a combination of IL17F rs763780/rs2397084/ IL17A rs2275913 (p = 0.04). The CG and CGA haplotype frequencies were significantly higher in the severe group. IL17A rs2275913, IL17F rs763780 and rs2397084 variants appear to have important effects on the immune response in COVID-19. In conclusion, variants of IL17A rs2275913, IL17F rs763780 and rs2397084 may be the predictive markers for the clinical course and potential immunomodulatory treatment options in COVID-19, a disease that has placed a significant burden on our country.     

Impact of the IL-17F,IL-23 and IL-23R on susceptibility and phenotype of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a disease characterized by excessive proinflammatory cytokine production and damage to multiple organ systems. To investigate the potential association between cytokine gene polymorphisms and SLE, we performed a case-control study based on Polish population. SLE patients and controls, were examined for IL-23A rs11171806?G/A and IL-23R (rs1884444?G/T, rs10489629?G/A) by TaqMan SNP genotyping assay, for IL-17F rs763780 A/G and rs2397084A/G using the PCR– RFLP method. An increased frequency of AG genotype as well as G allele of the IL-17F rs763780 was found in patients with SLE, as compared with healthy subjects (OR?=?3.947; p?=?0.001 and OR?=?3.538; p?=?0.002, respectively). Frequencies of the rs1884444 TT genotype (OR?=?138.1) and the rs1884444 T allele (OR?=?2.176) were also higher in SLE patients (both p?0.0001). Overall, weak LD was observed between the IL-17F rs763780 A/G and rs2397084 A/G polymorphisms (D'-0.003, r² – 0.000). From four possible haplotypes, frequencies of AG showed differences between both examined groups (p?0.0001). We also observed a weak LD between the IL-23R rs10489629G/A and rs1884444?G/T (D'-0.199, r² –0.026). The genotype–phenotype analysis showed significant association between the IL-17F rs2397084 and mean value of the hemoglobin (p?=?0.01), the IL-17F rs763780 and age (p?=?0.008) and lupus anticoagulant (p?=?0.09), the IL-23 rs11171806 and urea (p?=?0.08) and C3 complement (p?=?0.03), and the IL-23R rs1884444?G/T and activated partial thromboplastin time (p?=?0.06). Present findings indicated that IL-17F rs763780 A/G and IL-23R rs1884444?G/T polymorphisms may be involved in susceptibility to SLE in the Polish population.     

Associations between interleukin 17A and 17F polymorphisms and asthma susceptibility: A meta-analysis

Owing to their role in inflammatory reactions and immunological responses as well as their chromosomal location, interleukin (IL) 17A and 17F are regarded as candidate causal genes associated with asthma. The aim of this study was to determine whether IL17 polymorphisms are associated with susceptibility to asthma. We used the PubMed/Medline and Embase databases to search for studies reporting IL17 polymorphisms in patients with asthma and healthy controls. Meta-analyses were conducted to determine the associations between IL17A rs8193036 (−737C/T), rs2275913 (−197G/A), rs3819024 (A/G), rs3748067 (C/T), and rs4711998 (A/G) and IL17F rs763780 (7488A/G), rs2397084 (T/C), rs1889570 (C/T), rs11465553 (G/A), and rs1266828 (T/C) polymorphisms and asthma susceptibility. A total of 20 studies were included in this meta-analysis. Our results revealed the IL17A rs8193036 CC genotype was associated with asthma susceptibility (odds ratio [OR] = 1.490, 95% confidence interval [CI] = 1.027–2.161, p = .036). However, stratification by ethnicity indicated no association between this polymorphism and asthma in European and Asian subjects. Furthermore, no association was found between this polymorphism and asthma using the allele contrast, dominant or homozygous contrast models. No evidence of an association was found between any of the other IL17A and IL17F polymorphisms and asthma susceptibility in this meta-analysis. This meta-analysis showed that, among the studied polymorphisms, only the CC genotype of IL17A rs8193036 is associated with asthma susceptibility.     

Analysis of IL-17 gene polymorphisms in Chinese patients with dilated cardiomyopathy

Cardiomyopathy is one of the major causes of sudden death and/or progressive heart failure. Dilated cardiomyopathy (DCM), comprising 60% of the cases of identified cardiomyopathy, is the most common form of heart muscle disease. Interleukin 17 (IL-17) is a proinflammatory cytokine that has been implicated in the pathogenesis of various diseases. To evaluate the influence of IL-17A and IL-17F gene polymorphisms on the risk of DCM, a case-control study was conducted in a Chinese Han population. The TaqMan® SNP Genotyping Assay was used to genotype the SNP rs2275913 of IL-17A and SNP rs763780 of IL-17F in 288 DCM patients and 421 ethnicity-matched controls. No significant difference in genotypic and allelic frequencies between DCM patients and control subjects was observed. However, Results of stratified analysis revealed that rs763780 was associated with male DCM patients in a dominant genetic model (p = 0.031, OR = 1.83, 95% CI = 1.04–3.22). Our results suggest that the tested two IL-17 SNPs, rs2275913 and rs763780, are not found to be associated with DCM in the Chinese population studied.     

Association study of interleukin-19 rs2243188 polymorphism with systemic lupus erythematosus in a Chinese population

Abstract

The purpose of this study was to evaluate whether a single-nucleotide polymorphism (SNP), rs2243188 of interleukin-19 (IL-19), show significant evidence for association with SLE in a Chinese population. A total of 545 SLE patients and 613 healthy controls were collected in the present study. The genotyping of IL-19 rs2243188 polymorphism was detected by TaqMan allele discrimination assay on the 7300 real time polymorphism chain reaction system. The minor C allele of rs2243188, relative to the major A allele, appeared to have a significantly lower frequency in SLE patients (31.0%) as compared with controls (35.5%) (χ²?=?5.19, p?=?0.023). We also discovered a statistical significance in the dominant model (CC?+?CA versus AA: OR?=?0.755, 95% CI?=?0.598–0.953, p?=?0.018). However, no significant difference in genotype distribution was found between SLE patients and controls (p?=?0.056). Furthermore, an increased frequency of CC genotype were also detected in lupus nephritis (LN) groups as compared with non-LN groups (p?=?0.024). Besides, the individuals with CC genotype had a 2.201-fold higher risk for the susceptibility to LN than those A allele carriers (AA?+?CA) (p?=?0.006). Unfortunately, the analyses on the relationship of IL-19 rs2243188 with several clinical manifestations of SLE failed to find any significant results. In conclusion, our observations suggested the minor C allele of SNP rs2243188 might be a protective factor for SLE in a Chinese Han population. Moreover, the subgroup analysis highlighted that IL-19 rs2243188 SNP was associated with the susceptibility to LN patients.     

Interleukin-17A gene polymorphism is associated with susceptibility to gastric cancer

We conducted a study to investigate the role of three common SNPs in the IL-17A and IL-17F genes (rs2275913G>A, rs3748067C>T and rs763780T>C) in the development of gastric cancer, and their interaction with H.pylori infection. A total of 326 patients with gastric cancer and 326 control subjects were consecutively recruited between May 2012 and May 2014. Genotyping of IL-17A rs2275913G>A and rs3748067C>T and IL-17F rs763780T>C was performed in a 384-well plate format on the Sequenom MassARRAY platform. By logistic regression analysis, individuals carrying the GA and AA genotypes of IL-17 rs2275913G>A were significantly associated with an increased risk of gastric cancer when compared with GG genotype, and the adjusted Ors (95% CI) were 1.46 (1.03-2.06) for GA genotype and 2.57 (1.51-4.43) for AA genotype. We observed that the GA+AA genotype of rs2275913 was associated with an increased risk of gastric cancer among H.pylori infection subjects (OR=2.21, 95% CI=1.29-3.79). In conclusion, we found that there was a significant association between L-17A rs2275913G>A polymorphism and increased gastric cancer risk, especially in H.pylori infection subjects.     

Association of IL17 and IL23R gene polymorphisms with rheumatic heart disease in South Indian population

ABSTRACT

Background: IL-23/Th17 signaling pathway plays a crucial role in the cell-mediated immune response against bacterial infections and also in the pathogenesis of inflammatory and autoimmune diseases. Recent studies indicate that Th17 cell-associated cytokines are involved in the progression and maintenance of valvular lesions in rheumatic heart disease (RHD). Variants in the genes of cytokines that are potentially involved in Th17 response may influence interindividual differences in their expression levels, thereby contributing to the pathogenesis of immune-mediated diseases such as RHD.

Objective: The aim of the study is to investigate the association of IL17A, IL17F, and IL23R gene variants with the risk perception of RHD.

Methods: A total of 225 individuals (99 RHD patients and 126 healthy siblings) were recruited for the study. The IL17A (rs2275913), IL17F (rs763780), and IL23R (rs10889677) polymorphisms were determined by polymerase chain reaction restriction fragment length polymorphisms and amplification-refractory mutation system-polymerase chain reaction methods, respectively.

Results: The frequency of IL17A (rs2275913) A/A genotype was significantly high in pooled RHD patients (odds ratio [OR] = 2.76; p_c = 0.021), rheumatic fever (RF) patients (OR = 14.5; p_c = 0.0001), and mitral valvular lesions patients (OR = 2.74; p_c = 0.039) when compared to healthy siblings. However, the IL17F (rs763780) and IL23R (rs10889677) polymorphisms did not show any association with RHD.

Conclusions: The results suggest that IL17A (rs2275913) polymorphism is associated with the development of RF/RHD in South Indian population. Further studies are required to substantiate the association of these genes with the disease risk.     

IL-17F 基因多态性与类风湿关节炎发病风险关系的Meta 分析

目的:探讨白介素17F(IL-17F)基因多态性rs763780 和rs2397084 与类风湿关节炎(RA)易感性的关系。方法:计算机检索中国学术期刊全文数据库、万方数据库、中国生物医学文献数据库、Pubmed、Embase 以及Web of Science 中已发表的与RA 和IL-17F 基因多态性相关文献,进行Meta 分析。结果:纳入的5 项研究共收集RA 患者1 174 例(其中rs763780 含1 174 例,rs2397084 含985 例),正常对照966 例(rs763780 含966 例,rs2397084 含766 例)。Meta 分析结果显示,rs763780 与RA 密切相关(C vs.T:OR=1.74,95%CI =1.01-2.98,P =0.04;CC vs.TT:OR=3.17,95% CI =1.21-8.35,P =0.02;CT vs.TT:OR=1.80,95%CI =1.21-2.66,P =0.004;CC+CT vs.TT:OR=1.96,95% CI =1.35-2.83,P<0.001;CC vs.CT+ TT:OR=2.97,95%CI =1.13-2.66,P =0.03)。根据人种进行亚组分析发现,在欧洲人群中rs763780 与RA 密切相关,差异具有统计学意义。未发现rs2397084 与RA 之间的相关性。结论:IL-17F rs763780 是RA 的危险因素,IL-17F rs2397084 与RA 易感性是否有关仍不明确。     

Evaluation of IL17A expression and of IL17A,IL17F and IL23R gene polymorphisms in Brazilian individuals with periodontitis

The IL23/Th17 axis plays an important role in the pathogenesis of cell-mediated tissue damage caused either by autoimmunity or immune responses against bacterial infection. Single nucleotide polymorphisms in the IL17A, IL17F and IL23R genes have been associated with several inflammatory diseases. However, these polymorphisms have not yet been studied in periodontitis. The aim of present study was to evaluate the expression of IL17A and occurrence of the IL17A (rs2275913), IL17F (rs763780) and IL23R (rs11209026) gene polymorphisms in different clinical forms or severity of periodontitis in a sample of Brazilian individuals. Peripheral blood was obtained from 30 non-smoker individuals and analyzed by flow cytometry to determine IL-17 expression. Genomic DNA was obtained from oral swabs in 180 individuals and analyzed by Real-time PCR. The study group was composed by individuals without periodontitis (control), with aggressive periodontitis (AP) and with chronic periodontitis (CP). Higher frequency of IL17A+CD4+ T cells was observed in control group. The A+ genotype from IL17A (rs2275913) was associated with lack of disease. No association was found considering the IL17F and IL23R polymorphisms. Our data suggest that IL17A and the presence of IL17A (rs2275913) A allele are associated with the absence of periodontal disease.     

Association of IL-17A and IL-17F polymorphisms with gastric cancer risk in Asians: A meta-analysis

Increasing number of studies focused on the association of IL-17A rs2275913 and IL-17F rs763780 polymorphisms with gastric cancer (GC) risk. However, the results were inconsistent. To elucidate the exact association, we performed the present meta-analysis. Databases including PubMed, Web of knowledge and Chinese National Knowledge Infrastructure (CNKI) were systematically searched for potentially eligible literatures. Odds ratios (OR) and their 95% confidence interval (CI) were used to evaluate the strength of association. Eight studies for IL-17A rs2275913 (3345 cases and 4427 controls) and five studies for IL-17F rs763780 (1784 cases and 2592 controls) were finally included. The results indicated that individuals with AA genotype of IL-17A rs2275913 polymorphism were associated with increased GC risk compared with wild-type GG (OR = 1.61, 95% CI = 1.17–2.23, P = 0.004); A allele was significantly associated with increased GC risk compared with G allele (OR = 1.22, 95% CI = 1.06–1.41, P = 0.007). IL-17F rs763780 polymorphism was also significantly associated with increased GC risk (CC vs. CT: OR = 1.40, 95% CI = 1.04–1.88, P = 0.025; CT vs. TT: OR = 1.35, 95% CI = 1.16–1.58, P < 0.001; C allele vs. T allele: OR = 1.30, 95% CI = 1.15–1.47, P < 0.001). In summary, IL-17A rs2275913 A/G polymorphism and IL-17F rs763780 C/T polymorphism might be associated with increased GC risk in Asians. Further large-scale studies are still required to confirm the results of this meta-analysis.     

Association between interluekin-17 gene polymorphisms and the risk of cervical cancer in a Chinese population

We conducted a study to analyze the association of three common SNPs of IL-17A rs2275913 and rs3748067 and IL-17F rs763780 gene polymorphisms with the risk of cervical cancer in a Chinese population. Our study included 352 cervical cancer patients and 352 controls between January 2013 and December 2014. Genotyping of IL-17A rs2275913 and rs3748067 and IL-17F rs763780 genes was performed by multiplex PCR assays using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). By χ² test, there was significantly difference in the genotype distribution of IL-17A rs2275913 between cervical cancer patients and control subjects (χ²=11.45, P=0.003). By conditional logistic regression analysis, we found that individuals with the GA and AA genotypes were associated with an increased risk of cervical cancer when compared with the GG genotype in codominant model, and the adjusted Ors (95% CI) were 1.57 (1.13-2.18) and 2.01 (1.15-3.49), respectively. In dominant model, we found that the GA+AA genotype of rs2275913 was correlated with a moderate increased risk of cervical cancer compared with the GG genotype (OR=1.64, 95% CI=1.20-2.24). We only found significant interaction between rs2275913 polymorphism and HPV-16 or 18 infection in the risk of cervical cancer (P for interaction <0.05). In conclusion, our study suggests that IL-17A rs2275913 polymorphism may affect the development of cervical cancer in codominant and dominant models, and this gene polymorphism has interaction with HPV-16 or 18 infection.     

StIL-17 gene polymorphisms in the development of pulmonary tuberculosis

We conduct a case-control study to explore the possible association between IL-17 gene polymorphisms and development of TB. Methods: The study population comprised 428 TB subjects and 428 control subjects between January 2013 and June 2014. Genotyping analyses of IL-17A rs2275913 and rs3748067 and IL-17F rs763780 and rs9382084 were analyzed using polymerase chain reaction-restriction fragment length of polymorphism (PCR-RFLP). Results: The TB cases were more likely to have a habit of smoking when comparing with controls. By conditional logistic regression analysis, individuals carrying CC genotype of rs763780 were more likely to have a significantly increased risk of TB when compared with TT genotype. The OR (95% CI) for CC genotype of rs763780 was 2.98 (1.58-5.92). Conclusion: In conclusion, we suggest that rs763780 play a critical role in the etiology of TB. These findings could be helpful in identifying individuals at increased risk for developing TB.     

C1q rs292001 polymorphism and C1q antibodies in juvenile lupus and their relation to lupus nephritis

C1q deficiency is related strongly to systemic lupus erythematosus (SLE), but very few and inconsistent studies explored the single nucleotide polymorphisms of the C1q gene in relation to juvenile SLE (jSLE) and lupus nephritis (LN). The objective of this study was to analyse whether C1q rs 292001 polymorphism is associated with SLE and disease phenotype, especially nephritis, and to investigate the relation between this polymorphism and clinical data, treatment outcome, serum level of C1q protein and antibodies. Typing of C1q rs292001 polymorphism using restriction fragment length polymorphism and measuring serum levels of C1q protein and antibodies by enzyme-linked immunosorbent assay (ELISA) were performed for 130 children with SLE and 208 healthy controls. The A allele of C1q rs292001 was associated with jSLE and LN (P = 0·005 and 0·013, respectively) and the AA genotype was associated with jSLE (P = 0·036). Low serum levels of C1q protein were found in jSLE and LN (P < 0·001 and 0·009, respectively), and these levels were increased after treatment in patients with LN (P = 0·009) and active renal disease (P = 0·027). Higher titres of C1q antibodies were found in patients with LN (P = 0·015) and correlated negatively with C1q protein level (P < 0·001) and patient age (P = 0·04). The A allele and AA genotype of C1q rs292001 can be considered a susceptibility risk factor and the GG genotype could be considered protective for jSLE and LN in the studied cohort of Egyptian children. Decreased serum levels of C1q protein and increased titres of C1q antibodies may be involved in the pathogenesis of jSLE, especially LN.     

Interleukin-17A and -17F single nucleotide polymorphisms associate with susceptibility of asthma in Chinese Han population

Interleukin 17 (IL-17) plays important roles in the progression of asthma. Genetic variants in the Il-17 may influence the immunopathogenesis of many diseases. Many studies have investigated the relevance of IL-17 polymorphism with cancers or immune diseases, including asthma. In this study, single nucleotide polymorphisms (SNPs) of IL-17 were explored by PCR-RFLP and verified by sequencing method. The frequencies of genotypes and alleles were analyzed. Haplotypes were analyzed with the SHEsis online program. The relationship between the genotypes of SNPs and IgE level was also investigated. The False Discovery Rate (FDR) correction was performed (P-adjusted?<?0.05). The frequencies of A allele, GA and (GA?+?AA) genotype of rs3748067 were significantly higher in asthma patients. As for rs763780, the C allele in patients was more frequent than healthy controls. In addition, we found C carriers (CT?+?CC) were significantly higher in asthma patients. We further found that the haplotype CT for IL-17F (rs763780/rs2397084) was associated with an increased susceptibility of asthma, but this association did not survive after FDR correction. The level of serum total IgE in mutant group (GA?+?AA) of rs3748067 was significantly higher than the wild genotype (GG) group and control group. These results suggested that IL-17 SNPs, but not haplotypes may be associated with the susceptibility of asthma in Chinese Han population from central China.     

Influence of IL17A polymorphisms (rs2275913 and rs3748067) on the susceptibility to ulcerative colitis

Interleukin-17A plays a role in tissue inflammation by inducing release of proinflammatory and neutrophil-mobilizing cytokines. We investigated the association between ulcerative colitis (UC) and polymorphisms of IL17A, rs2275913 (?197 G > A), and rs3748067 (*1249 C > T). The study was performed in 475 healthy subjects (controls) and 202 with UC (UC cases), including 113 controls and 64 UC cases from previous study. We employed the multiplex PCR-SSCP method to detect gene polymorphisms. The minor allele frequency of rs2275913 was significantly higher but that of rs3748067 was significantly lower in UC cases than controls. The rs2275913 minor homozygote (AA) had an increased risk of the development of UC, whereas rs3748067 minor carrier (CT + TT) had decreased risks for the development of UC. When compared with LR group (rs2275913 GG + GA with rs3748067 CT + TT), HR group (rs2275913 AA with rs3748067 CC) had a more increased risk of the development of UC (OR, 3.38; p = 0.0007). The polymorphisms of IL17A were associated with the noncontinuous and pancolitis phenotypes of UC. Our results suggest that IL17A polymorphisms (both rs2275913 and rs3748067) influence the susceptibility to and pathophysiological features of UC, coordinately.     

Association of interleukin-17A and -17F gene single-nucleotide polymorphisms with autoimmune thyroid diseases

Th17 lymphocyte and its relative cytokines have been shown to play an important role in autoimmune thyroid diseases (AITD). The aim of this study was to investigate the association between IL-17A and IL-17F gene polymorphisms and two main types of AITD, Graves' disease (GD) and Hashimoto's thyroiditis (HT). Whole blood specimens and clinical data were collected from 508 AITD patients (326 with GD and 182 with HT) and 224 age- and gender-matched healthy controls, respectively. IL-17A (rs2275913, rs8193037, rs3819025) polymorphism was determined using DNA sequencing method and IL-17F/rs763780 polymorphism was assayed by polymerase chain reaction-restriction fragment length polymorphism (PCR -RFLP). The results indicated that the frequencies of IL-17F/rs763780 genotypes in patients with GD and HT differed significantly from their controls (P = 0.013 and P = 0.005, respectively); the G allele frequencies were also significantly higher in the patient groups than the control groups (P = 0.002 and 0.001, respectively). For IL-17A/rs2275913 and rs8193037 SNP, no significant difference was observed in patients with either GD or HT compared to the control groups (P>0.05). Interestingly, for rs3819025, the frequency of A allele was lower in patients with GD than controls (P = 0.011). The frequencies of haplotype AGGG and GGGG in patients with GD and HT were significantly higher than in controls (P = 0.012, P = 0.019, P = 0.017 and P = 0.029, respectively). In conclusion, the results indicate that IL-17F/rs763780 polymorphisms may affect the susceptibility to AITD, and IL-17A/rs3819025 SNP is likely a protective factor to GD in the Chinese population.     

IL8 and IL17A polymorphisms associated with multibacillary leprosy and reaction type 1 in a mixed population from southern Brazil

We evaluated the influence of the IL8 T‐738A (nonidentified rs), IL8 T‐353A (rs4073), IL17A G197A (rs2275913), and IL17F T7488C (rs763780) single‐nucleotide polymorphisms on leprosy. The AA genotype of IL8 T‐353A was observed as a risk factor for multibacillary leprosy, regardless of gender and age‐of‐onset of disease, considering the recessive model (OR, 3.8; 95% CI, 1.1–13.5; P, 0.023). Furthermore, the AA genotype of IL17A G197A was associated with leprosy type 1 reaction (OR, 2.4; 95% CI, 1.1–5.1; P, 0.026) when compared to the group without reaction, which was adjusted for gender and age‐of‐onset of disease by the model log additive. These results indicate association of IL8 and IL17A polymorphisms with the progression to multibacillary leprosy and with the type 1 reaction, respectively.     

Polymorphisms in Th17-related genes and the pathogenesis of autoimmune thyroid disease

Abstract

The prognosis of autoimmune thyroid disease (AITD) including Graves’ disease (GD) and Hashimoto’s disease (HD) is difficult to predict. We previously suggested that Th17 cells may be associated with the pathogenesis of AITD. However, the association between gene polymorphisms in Th17-related genes and the prognosis of AITD was not clarified. To clarify this association, we genotyped 12 polymorphisms in 11 Th17-related genes (IL1Ra, IL6R, IL17R, IL21R, IL23R, CCR6, SOCS3, RORC, IL17A, IL17F and IL21) in 142?HD patients including 58 patients with severe HD and 48 patients with mild HD, 170 patients with GD including 81 patients with intractable GD and 49 patients with GD in remission, and 84 healthy volunteers. The frequency of the IL17F rs763780 T allele was higher in patients with severe HD than in patients with mild HD (p?=?.008). The frequency of the IL17R rs9606615 T allele was higher in patients with HD than in normal subjects (p?=?.011). The frequencies of the SOCS3 rs4969170 AA genotype, CCR6 rs3093024 AA genotype, and IL21 rs907715 AA genotype were higher in patients with intractable GD than in patients with GD in remission (p?=?.035, p?=?.002 and p?=?.030, respectively). In conclusion, IL17R rs9607715 and IL17F rs763780 polymorphisms are associated with the susceptibility and severity of HD, respectively. IL21 rs907715, SOCS3 rs4969170 and CCR6 rs3093024 polymorphisms are associated with the intractability of GD.     

Genetic polymorphisms of interleukin 17A and interleukin 17F and their association with inflammatory bowel disease in a Chinese Han population

Objective

Interleukin-17A and interleukin-17F (IL-17A and IL-17F) are candidate genes for chronic inflammatory disease. We investigated the association between IL17A/F gene polymorphisms and susceptibility to and clinical features of inflammatory bowel disease (IBD).

Methods

A total of 270 ulcerative colitis (UC) patients, 82 Crohn’s disease (CD) patients and 268 healthy controls were recruited in this study. Genomic DNA was extracted and analyzed for IL17A/F gene polymorphisms using ligase detection reaction allelic technology.

Results

Compared to the controls, the mutant allele C for IL17F rs763780 was significantly more common in CD patients [14.0 vs 8.4 %, P = 0.033, odds ratio (OR) 1.18, 95 % confidence interval (CI) 1.41–3.04] and was associated with the disease lesion location. This variant of IL17F rs763780 also had a weak correlation with the age of UC onset (P = 0.05, OR 0.97, 95 % CI 0.94–1.00). The IL17A (rs2275913, G-197A) variant had a weak association with the severity of disease: patients with the mutant allele A tended to suffer mild active UC. The haplotype (GGTT) of IL17A formed with four single nucleotide polymorphisms (rs2275913, rs8193037, rs8193038, and rs3804513) was associated with an increased risk of UC (P = 0.034, OR 4.58, 95 % CI 1.54–13.64).

Conclusions

The IL17F (rs763780, 7488T/C) variant was associated with an increased risk for the development of CD, and affected some clinical features of UC and CD. The IL17A (rs2275913, G-197A) variant had a weak association with the severity of UC. There was a risk haplotype in IL17A which could increase the risk of UC.     

Interleukin-17F and interleukin-6 gene polymorphisms in Asian Indian patients with Takayasu arteritis

Objectives

To assess genetic association between single nucleotide polymorphisms (SNPs) in genes encoding T-helper cytokines and Takayasu Arteritis (TA) susceptibility in Asian Indian population.