Association of STAT4 rs7574865 polymorphism with autoimmune diseases: a meta-analysis

An immunogenomic exome landscape of triple positive primary antiphospholipid patients

Primary antiphospholipid syndrome is characterized by thrombosis and autoantibodies directed against phospholipids or associated proteins. The genetic etiology of PAPS remains unknown. We enrolled 21 patients with thromboembolic events associated to lupus anticoagulant, anticardiolipin and anti β2 glycoprotein1 autoantibodies. We performed whole exome sequencing and a systematic variant-based analysis in genes associated with thrombosis, in candidate genes previously associated with APS or inborn errors of immunity. Data were compared to public databases and to a control cohort of 873 non-autoimmune patients. Variants were identified following a state-of-the-art pipeline. Enrichment analysis was performed by comparing with the control cohort. We found an absence of significant HLA bias and genetic heterogeneity in these patients, including when testing combinations of rare variants in genes encoding for proteins involved in thrombosis and of variants in genes linked with inborn errors of immunity. These results provide evidence of genetic heterogeneity in PAPS, even in a homogenous series of triple positive patients. At the individual scale, a combination of variants may participate to the breakdown of B cell tolerance and to the vessel damage.

Association of STAT4 Gene Polymorphisms (rs10181656, rs7574865, rs7601754, rs10168266) and Serum STAT4 Levels in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a progressive degenerative disease that affects the central part of the retina: the macula. AMD is the most common cause of central vision loss in industrialized countries. Increasing attention is being paid to the study of genetic factors that may influence the manifestation of AMD. STAT4 protein is involved in the pathogenesis of numerous inflammatory processes, so we decided to investigate the association between STAT4 gene polymorphisms (rs10181656, rs7574865, rs7601754, and rs10168266) and age-related macular degeneration.

PURPOSE

To investigate the association between STAT4 (rs10181656, rs7574865, rs7601754, and rs10168266) gene polymorphisms and STAT4 serum levels in patients with age-related macular degeneration.

METHODS AND PARTICIPANTS

The study included 150 individuals with early AMD, 150 individuals with exudative AMD, and 200 healthy subjects. DNA was extracted from peripheral blood leukocytes using the DNA salting-out method, and the genotyping was performed using a real-time polymerase chain reaction (RT-PCR) method. STAT4 serum levels were evaluated using the ELISA method. Statistical analysis was performed using "IBM SPSS "Statistics 29.0" software".

RESULTS

The study revealed no statistically significant differences in the distribution of genotypes and alleles for the STAT4 polymorphisms (rs10181656, rs7574865, rs7601754, and rs10168266) between patients with AMD and the control group. Similarly, a gender-based analysis did not yield any significant differences in the genotype or allele frequencies. Age group comparisons also showed no statistically significant variations in the presence of these STAT4 polymorphisms between AMD patients and the control group. However, notably, individuals with exudative AMD displayed lower levels of serum STAT4 in comparison to the control group (median (IQR): 0.118 (0.042) vs. 0.262 (0.385), p = 0.005).

CONCLUSION

Investigating STAT4 gene polymorphisms (rs10181656, rs7574865, rs7601754, and rs10168266) did not reveal a significant association with AMD. However, further analysis demonstrated intriguing findings regarding serum STAT4 levels. Exudative AMD patients with at least one G allele of the STAT4 rs10181656 exhibited significantly lower serum STAT4 levels than the control group subjects (p = 0.011). Similarly, those with at least one T allele of STAT4 rs10168266 had lower serum STAT4 levels compared to the control group subjects (p = 0.039). These results suggest a potential link between specific STAT4 genotypes and serum STAT4 levels in exudative AMD patients, shedding light on a novel aspect of the disease.

Assessing the association of rs7574865 STAT4 gene variant and type 1 diabetes mellitus among Egyptian patients

Background

Variants in the signal transducer and activator of transcription 4 (STAT4) gene have an important role in the incident of multiple autoimmune diseases including type 1 diabetes mellitus (T1D). It is a genetically related auto-immune disorder that resulted from T cell-mediated destruction of pancreatic cells that are in control for the production of insulin in the blood. The current study aimed to clarify the role of STAT4 (rs7574865) variant allelic and genotypic variations in the susceptibility to type 1 diabetes among Egyptians by using the real-time PCR.

Results

A total of 100 patients and 100 controls were genotyped for rs7574865, and the biochemical and anthropometric parameters were measured to show that type 1 diabetic patients had significantly higher levels of HbA1c and triglycerides compared to non-diabetic individuals (P < 0.05). And genetically, the T allele and GT genotype have a significant correlation with diabetes type 1.

Conclusion

It was confirmed by this study that the rs7574865 T allele and GT genotype have a significant correlation with diabetes type 1 incidence among Egyptian patients.

The pre-clinical phase of rheumatoid arthritis: From risk factors to prevention of arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease considered as a multistep process spanning from the interaction of genetic (e.g., shared epitope or non-HLA loci), environmental and behavioral risk factors (e.g., smoking) leading to breaking immune tolerance and autoimmune processes such as the production of autoantibodies (e.g., antibodies against citrullinated proteins ACPA or rheumatoid factors, RF), development of the first symptoms without clinical arthritis, and, finally, the manifestation of arthritis. Despite the typical joint involvement in established RA, the pathogenesis of the disease likely begins far from joint structures: in the lungs or periodontium in association with citrullination, intestinal microbiome, or adipose tissue, which supports normal findings in synovial tissue in ACPA+ patients with arthralgia. The presence of ACPA is detectable even years before the first manifestation of RA. The pre-clinical phase of RA is the period preceding clinically apparent RA with ACPA contributing to the symptoms without subclinical inflammation. While the combination of ACPA and RF increases the risk of progression to RA by up to 10 times, increasing numbers of novel autoantibodies are to be investigated to contribute to the increased risk and pathogenesis of RA. With growing knowledge about the course of RA, new aspiration emerges to cure and even prevent RA, shifting the "window of opportunity" to the pre-clinical phases of RA. The clinical definition of individuals at risk of developing RA (clinically suspect arthralgia, CSA) makes it possible to unify these at-risk individuals' clinical characteristics for "preventive" treatment in ongoing clinical trials using mostly biological or conventional synthetic disease-modifying drugs. However, the combination of symptoms, laboratory, and imaging biomarkers may be the best approach to select the correct target at-risk population. The current review aims to explore different phases of RA and discuss the potential of (non)pharmacological intervention aiming to prevent RA.

Genetic risk factors for autoimmune hepatitis: implications for phenotypic heterogeneity and biomarkers for drug response

Autoimmune hepatitis (AIH) is a rare chronic progressive liver disease with autoimmune features. It mainly affects middle-aged women. AIH is occasionally complicated with liver cirrhosis that worsens the prognosis. Genetic and environmental factors are involved in the pathogenesis of AIH. Genetic studies of other diseases have been revealing of pathogenesis and drug efficacy. In this review, we summarize the genetic risk factors for AIH, including human leukocyte antigen (HLA) and non-HLA genes. A genome-wide association study (GWAS) on European AIH revealed the strongest associations to be with single nucleotide variants (SNVs) in HLA. Predisposing alleles for AIH were DRB1*03:01 and DRB1*04:01 in Europeans; DRB1*04:04, DRB1*04:05, and DRB1*13:01 in Latin Americans; and DRB1*04:01 and DRB1*04:05 in Japanese. Other risk SNVs in non-HLA genes for AIH were found by a candidate gene approach, but several SNVs were confirmed in replication studies. Some genetic factors of AIH overlapped with those of other autoimmune diseases. Larger-scale GWASs of other ethnic groups are required. The results of genetic studies might provide an explanation for the phenotypic heterogeneity of AIH and biomarkers for drug responses.

Etiological Association Between Psoriasis and Thyroid Diseases

Psoriasis is a chronic relapsing/remitting autoimmune disease affecting skin and fingernails. It is associated with many other autoimmune diseases such as rheumatoid arthritis, celiac disease, Crohn's disease, and thyroid diseases. Two important autoimmune thyroid diseases - Hashimoto's thyroiditis (hypothyroidism) and Grave's disease (hyperthyroidism) - affect the body's significant organs such as the brain, muscles, digestive function, and the skin. Although some studies have established the connection between psoriasis and thyroid diseases with autoimmunity, our article provides an in-depth analysis of the connection between these two diseases and other common etiological factors associated with them, along with autoimmunity.

We reviewed articles from PubMed using regular keywords and Medical Subject Headings (MeSH) keywords and finalized 45 articles to find an association between these two diseases. These articles showed that this association is more prevalent in obese patients and late-onset psoriasis. Most of the articles showed a positive association, but few articles showed no connection between them. However, there is no concrete explanation to prove the association due to limited research; additional studies are necessary. It requires the attention of both clinicians and researchers to develop a universal drug that will work on both diseases, and also thyroid evaluation could be included in psoriatic patient care so that there is a possibility to decrease cost and efforts while treating these diseases. 

Genetic Susceptibility to Systemic Sclerosis in the Greek-Cypriot Population: A Pilot Study

Background: Systemic Sclerosis (SSc), also known as scleroderma, is an autoimmune rheumatic disease, which is clinically subdivided into two major subgroups; limited (lcSSc) and diffuse cutaneous scleroderma (dcSSc). Even though the SSc etiologies remains unclear, some HLA and non-HLA genetic variants have been associated with the disease. Aim: This study was designed to evaluate the associations between several HLA-related genetic variants and SSc in the Greek-Cypriot population. Methods: Forty-one SSc patients and 164 controls were genotyped at 18 selected single nucleotide polymorphisms (SNPs) using restriction fragment length polymorphism analyses, Sanger sequencing, and a multiplex SNaPshot minisequencing assay. Logistic regression analysis under the log-additive model was used to evaluate all possible associations between these SNPs and SSc; nominal statistical significance was assumed at p < 0.05. Results: Associations of SSc with SNPs rs3117230, rs3128930, and rs3128965 within the HLA-DPB1 and HLA-DPB2 regions were observed in the Greek-Cypriot population at the level of p < 0.05. However, none of these associations survived a Bonferroni correction. The direction of the effect is consistent with the direction reported in previous studies. In addition, allele frequencies of the majority of the selected SNPs in the Greek-Cypriot population are similar to those reported in the European population. Conclusion: This study initiates the genetic investigation of SSc in the Greek-Cypriot population, a relatively small newly investigated population. Further investigation with a larger sample size and/or additional SSc susceptibility loci may confirm the association of some of these variants with SSc in the Greek-Cypriot population that could potentially be used for predictive testing.

STAT4 silencing underlies a novel inhibitory role of microRNA-141-3p in inflammation response of mice with experimental autoimmune myocarditis

As an inflammatory disease afflicting the heart muscle, autoimmune myocarditis (AM) represents one of the foremost causes of heart failure. Accumulating evidence has implicated microRNAs (miRNAs) in the process of inflammation and autoimmunity. Hence, the current study aimed to investigate the mechanism by which miR-141-3p influences experimental AM (EAM). An EAM mouse model was established using 6-wk old male BALB/c mice, after which the expression of miR-141-3p and STAT4 was measured. Gain-of-function and loss-of-function investigations were performed to identify the functional role of miR-141-3p and STAT4 in EAM. Heart weight-to-body weight ratio, cardiac function, and degree of inflammation, as well as the levels of inflammation factors (IFN-γ, TNF-α, IL-2, IL-6, and IL-17) in the serum were detected. STAT4 was subsequently verified to be upregulated, and miR-141-3p was downregulated in the EAM mice. Furthermore, the overexpression of miR-141-3p or silencing of STAT4 was observed to reduce the heart weight-to-body weight ratio of EAM mice and improve cardiac function, while alleviating the degree of inflammatory cell infiltration in the myocardial tissue. Meanwhile, the overexpression of miR-141-3p was identified to diminish serum inflammatory factor levels by downregulating STAT4. Additionally, miR-141-3p could bind to STAT4 to downregulate its expression, ultimately mitigating inflammation and inducing an anti-inflammatory effect in EAM mice. Taken together, upregulation of miR-141-3p alleviates the inflammatory response in EAM mice by inhibiting STAT4, providing a promising intervention target for the molecular treatment of AM.NEW & NOTEWORTHY miR-141-3p is poorly expressed, and STAT4 is upregulated in experimental autoimmune myocarditis (EAM) mice. Overexpressing miR-141-3p inhibits EAM. miR-141-3p binds to and suppresses STAT4 expression. miR-141-3p overexpression inhibits inflammatory factors by downregulating STAT4. This study provides new insights into the treatment of autoimmune myocarditis.

Genetic implications in the pathogenesis of rheumatoid arthritis; an updated review

Three important factors, including genetics, environment factors and autoimmunity play a role in the pathogenesis of rheumatoid arthritis (RA). The heritability of RA has been accounted to be 50-60%, while the HLA involvement in heritability of the disease has been accounted to be 10-40%. It has been documented that shared epitope (SE) alleles, such as HLA-DRB1*01 and DRB1*04, some HLA alleles like HLA-DRB1*13 and DRB1*15 are connected to RA susceptibility. An advanced classification of SE categorizes SE alleles into four main groups namely, S1, S2, S3D, and S3P. The S2 and S3P groups have been linked to susceptibility of seropositive RA. Various genome-wide association studies (GWAS) have discovered many susceptibility loci implicated in pathogenesis of RA. Some of the important single nucleotide polymorphisms (SNPs) linked to RA are TRAF1, STAT4, CTLA4, IRF5, CCR6, PTPN22, IL23R, and PADI4. HLA and non-HLA genes may discriminate anti-cyclic citrullinated peptide (anti-CCP) antibody-positive and anti-CCP-negative RA groups. Furthermore, risk of the disease has also been linked to environmental agents, mainly cigarette smoking. Pharmacogenomics has also confirmed SNPs or genetic patterns that might be linked to drugs responses. Different aspects of genetic involvement in the pathogenesis, etiology, and RA complications are reviewed in this article.

High-throughput inference of pairwise coalescence times identifies signals of selection and enriched disease heritability

Interest in reconstructing demographic histories has motivated the development of methods to estimate locus-specific pairwise coalescence times from whole-genome sequence data. Here we introduce a powerful new method, ASMC, that can estimate coalescence times using only SNP array data, and is orders of magnitude faster than previous approaches. We applied ASMC to detect recent positive selection in 113,851 phased British samples from the UK Biobank, and detected 12 genome-wide significant signals, including 6 novel loci. We also applied ASMC to sequencing data from 498 Dutch individuals to detect background selection at deeper time scales. We detected strong heritability enrichment in regions of high background selection in an analysis of 20 independent diseases and complex traits using stratified LD score regression, conditioned on a broad set of functional annotations (including other background selection annotations). These results underscore the widespread effects of background selection on the genetic architecture of complex traits.

A plausibly causal functional lupus-associated risk variant in the STAT1-STAT4 locus

Systemic lupus erythematosus (SLE or lupus) (OMIM: 152700) is a chronic autoimmune disease with debilitating inflammation that affects multiple organ systems. The STAT1-STAT4 locus is one of the first and most highly replicated genetic loci associated with lupus risk. We performed a fine-mapping study to identify plausible causal variants within the STAT1-STAT4 locus associated with increased lupus disease risk. Using complementary frequentist and Bayesian approaches in trans-ancestral Discovery and Replication cohorts, we found one variant whose association with lupus risk is supported across ancestries in both the Discovery and Replication cohorts: rs11889341. In B cell lines from patients with lupus and healthy controls, the lupus risk allele of rs11889341 was associated with increased STAT1 expression. We demonstrated that the transcription factor HMGA1, a member of the HMG transcription factor family with an AT-hook DNA-binding domain, has enriched binding to the risk allele compared with the non-risk allele of rs11889341. We identified a genotype-dependent repressive element in the DNA within the intron of STAT4 surrounding rs11889341. Consistent with expression quantitative trait locus (eQTL) analysis, the lupus risk allele of rs11889341 decreased the activity of this putative repressor. Altogether, we present a plausible molecular mechanism for increased lupus risk at the STAT1-STAT4 locus in which the risk allele of rs11889341, the most probable causal variant, leads to elevated STAT1 expression in B cells due to decreased repressor activity mediated by increased binding of HMGA1.

STAT4 gene polymorphism in two major autoimmune diseases (multiple sclerosis and juvenile onset systemic lupus erythematosus) and its relation to disease severity

Background

Multiple sclerosis (MS) and systemic lupus erythematosus (SLE) are chronic autoimmune mediated diseases with strong genetic and environmental components. The aim of this study is to evaluate the association of STAT4 gene polymorphism with multiple sclerosis (MS) and juvenile onset systemic lupus erythematosus (JO-SLE) and its relation to disease severity.

Methods

Group 1 consisted of 40 MS patients while group 2 included 40 JO-SLE patients. Forty healthy volunteers (controls) were included in this study. STAT4 genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results

The STAT4 CC genotype and GC genotype frequencies were significantly more detected in MS and JO-SLE patients than in controls. The frequency of the STAT4 C allele was significantly higher in patients with MS and those with JSLE compared to controls. Malar rash, photosensitivity, and hair falling were significantly more detected in CC subtype. Malar rash, photosensitivity, and hair falling were significantly more detected in CC subtype. Increased 24-h protein in urine (mg/24 h) and ANA positivity, anti-ds-DNA, anti Sm antibodies’ detection and decreased C3 and C4 levels showed a significantly difference in CC patients. Meanwhile, only increased 24-h protein in urine (mg/24 h) and ANA positivity were significantly more detected in GC patients. STAT4 CC genotype showed a significant increase in the SLE activity index (SLEAI) score and damage index as compared to the STAT4 GG genotype patients. No significant difference was detected in MS Kurtzke’s Expanded Disability Status Scale (EDSS) comparing different STATE 4 genotypes.

Conclusions

STAT4 polymorphism was significantly associated with MS and JO-SLE. Though homozygous JO-SLE patients are more risky for severe disease manifestations, homozygous MS patients are not risky for severe disease disability.

Type I interferon in rheumatic diseases

The type I interferon pathway has been implicated in the pathogenesis of a number of rheumatic diseases, including systemic lupus erythematosus, Sjögren syndrome, myositis, systemic sclerosis, and rheumatoid arthritis. In normal immune responses, type I interferons have a critical role in the defence against viruses, yet in many rheumatic diseases, large subgroups of patients demonstrate persistent activation of the type I interferon pathway. Genetic variations in type I interferon-related genes are risk factors for some rheumatic diseases, and can explain some of the heterogeneity in type I interferon responses seen between patients within a given disease. Inappropriate activation of the immune response via Toll-like receptors and other nucleic acid sensors also contributes to the dysregulation of the type I interferon pathway in a number of rheumatic diseases. Theoretically, differences in type I interferon activity between patients might predict response to immune-based therapies, as has been demonstrated for rheumatoid arthritis. A number of type I interferon and type I interferon pathway blocking therapies are currently in clinical trials, the results of which are promising thus far. This Review provides an overview of the many ways in which the type I interferon system affects rheumatic diseases.

[Molecular genetic examination for dry eye syndrome prognosis]

The article reviews the results of Russian and foreign studies concerning the search of susceptibility genes for widespread multifactorial diseases: Sjogren's syndrome and rheumatoid arthritis. Studying regularity patterns of genome changes in autoimmune processes with ophthalmic manifestations and their correlation with the severity of dry keratoconjunctivitis will contribute to a better understanding of the etiology and pathogenesis of eye manifestations of the diseases, and will also allow the development of new effective methods of diagnosis and targeted therapy.

Lack of Association between STAT4 Single Nucleotide Polymorphisms and Iranian Juvenile Rheumatoid Arthritis Patients

Juvenile rheumatoid arthritis (JRA) is a common chronic systemic autoimmune disease in children. Single nucleotide polymorphisms (SNPs) of signal transducer and activator of transcription 4 (STAT4) gene are suspected to have association with the risk of autoimmune diseases. Previous investigations have indicated that the STAT4 rs7574865 T allele was significantly associated with rheumatoid arthritis. In this study, we aimed to evaluate the association of STAT4 SNPs with JRA in Iranian population. T allele of STAT4 rs7574865 SNP was less frequent in patients than in controls, and the difference was not significant (p = 0.19, OR = 0.72, 95% CI: 0.44 -1.17). In addition, G allele of this SNP was frequent but not significant in JRA patients (p = 0.19, OR = 1.38, 95% CI: 0.85-2.25). Neither alleles nor genotypes of rs7601754 SNP of STAT4 gene demonstrated associations with JRA. We recognize that gene variants of STAT4 did not affect JRA susceptibility in Iranian population.

Targeting the programmed cell death-1 pathway in rheumatoid arthritis

Since the introduction of TNF-α inhibitors and other biologic agents, the clinical outcome for many treated rheumatoid arthritis patients has significantly improved. However, there are still a substantial proportion of patients that are intolerant, or have inadequate responses, with current agents that have become the standards of care. While the majority of these agents are designed to affect the inflammatory features of the disease, there are also agents in the clinic that instead target lymphocyte subsets (e.g., rituximab) or interfere with lymphocyte co-receptor signaling pathways (e.g., abatacept). Due in part to their ability to orchestrate downstream inflammatory responses that lead to joint damage and disease progression, pathogenic expansions of T and B lymphocytes are appreciated to play key roles in the pathogenesis of rheumatoid arthritis. New insights into immune regulation have suggested novel approaches for the pharmacotherapeutic targeting of lymphocytes. In this review, we discuss deepening insights into human genetics and our understanding of the interface with rheumatoid arthritis pathogenesis providing a strong rationale for exploiting the co-inhibitory receptor programmed cell death-1 signaling pathway as a better approach for the treatment of this chronic, often progressive destructive joint disease.

Association of STAT4 and PTPN22 polymorphisms and their interactions with type-1 autoimmune hepatitis susceptibility in Chinese Han children

AIMS

To investigate the impact of signal transducer and activator of transcription 4 (STAT4) and the protein tyrosine phosphatase N22 (PTPN22) gene single nucleotide polymorphisms (SNPs), gene-gene interactions and haplotype on type-1 Autoimmune Hepatitis (AIH) risk.

RESULTS

Logistic regression analysis showed that type 1 AIH was significantly higher in carriers of T allele of rs7574865 than those with GG genotype (P- value less than 0.001), higher in carriers of C allele of rs7582694 than those with GG genotype (P- value < 0.001), and lower in carriers of T allele of rs2476601 than those with CC genotype (P- value < 0.001). GMDR model indicated a significant two-locus model (p = 0.0100) involving rs7582694 and rs2476601. Participants with GC or CC of rs7582694 and CC of rs2476601 genotype have the highest type 1 AIH risk (P- value < 0.001), after covariates adjustment. Haplotype containing the rs7582694-C and rs7574865-T alleles were associated with a statistically increased type 1 AIH risk (P < 0.001).

MATERIALS AND METHODS

Logistic regression was performed to investigate association between SNPs within STAT4 and PTPN22 gene and susceptibility to type 1 AIH. Generalized multifactor dimensionality reduction (GMDR) was used to screen the best interaction combinations among the 4 SNPs.

CONCLUSIONS

We conclude that rs7574865 and rs7582694 in STAT4 gene minor alleles, interaction between rs7582694 and rs2476601, and haplotype containing the rs7582694-C and rs7574865-T alleles are associated with increased type 1 AIH risk, but rs2476601 in PTPN22 gene minor allele is associated with decreased type 1 AIH risk.

Effect of donor STAT4 polymorphism rs7574865 on clinical outcomes of pediatric acute leukemia patients after hematopoietic stem cell transplant

STAT4 polymorphism, rs7574865 is linked to various autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. Its T minor allele is associated with higher STAT4 mRNA and protein expression, indicating a stronger skewed immune response than the norm. Although widely studied in autoimmune disease patients and the general population, its effect on immunocompromised subjects is still unknown. Especially in situations, i.e. post-hematopoietic stem cell transplantation (post-HSCT), where control of the immune response is crucial. Hence, this study investigates if the presence of the T minor allele in donors would affect immunological response and clinical outcomes post-HSCT. Samples from 161 pediatric patients who underwent allogeneic HSCT for acute leukemia and showed complete chimerism by donor cells were obtained. Six clinical outcomes were investigated; hepatic veno-occlusive disease, acute graft-vs-host disease, chronic graft-vs-host disease, cytomegalovirus (CMV) infection, relapse and overall survival. The TT genotype was found to be significant in the occurrence of CMV infection (P=0.049), showing higher incidence of CMV infection compared to the others. Multivariate analysis confirmed that association of the TT genotype is independent from other variables in CMV infection occurrence (P=0.010). This is the first study on STAT4 polymorphism rs7574865 in allogeneic HSCT as well as immunocompromised patients. As the TT genotype is associated with autoimmune diseases, our results seem at a paradox with current evidence hinting at a different role of STAT4 in normal circumstances versus immunocompromised patients. Further investigation is needed to elicit the reason behind this and discover novel applications for better post-transplant outcomes.

STAT4 confers risk for rheumatoid arthritis and systemic lupus erythematosus in Mexican patients

STAT4 has been consistently associated with several autoimmune diseases, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The aim of this study was to determine whether the STAT4 rs7574865G/T polymorphism confers susceptibility for RA and SLE in a sample of Mexican patients. This study included 869 individuals: 415 patients with RA, 128 patients with SLE, and 326 controls. Genotyping using TaqMan probes showed an association between the STAT4 rs7574865G/T polymorphism and RA (GG vs. TT: OR 1.99, p=0.0009; G vs. T: OR 1.42, p=0.0009) and SLE (GG vs. TT: OR 2.98, 0.0003; G vs. T: OR 1.74, p=0.0002). Gender stratification showed an association with RA (GG vs. TT: OR 1.99, 95% CI 1.3-3.1, p=0.002; G vs. T: OR 1.42, 95% CI 1.1-1.8, p=0.002) and SLE (GG vs. TT: OR 3.3, 95% CI 1.7-6.2, p=0.0002; G vs. T: OR 1.8, 95% CI 1.3-2.4, p=0.0002) in women. Thus, the STAT4 rs7574865G/T polymorphism confers risk for RA and SLE in the Mexican population.

Contribution of the STAT4 rs7574865 gene polymorphism to the susceptibility to autoimmune thyroiditis in healthy Turk population and psoriatic subgroups

Introduction

STAT4 is an important transcription factor that activates gene transcription as a response to cytokines. Recently, the influence of STAT4 gene on autoimmune disease has been widely studied in many different immune-related diseases. Autoimmune, metabolic and cardiovascular disorders are more common in psoriatic patients. STAT4 may be a unique gene that switches on in autoimmune-related thyroid disease in psoriatic patients.

The aim of the study: To explore the association of a STAT4 rs7574865 polymorphism to autoimmune thyroid diseases in the general Turkish population and psoriatic subgroups.

Material and methods

A total of 132 psoriatic patients and 118 non-psoriatic volunteers were genotyped for STAT4 rs7574865 using real time PCR. Twenty-four of the psoriatic patients and 15 of the non-psoriatic volunteers have autoimmune-related thyroid diseases.

Results

The prevalence of the T allele [OR = 4.37; 95% CI: 1.05-19; p = 0.03] of the STAT4 rs7574865 was higher in individuals with autoimmune-related thyroid diseases among the all non-psoriatic volunteers. The volunteers with autoimmune-related thyroid diseases has an increased allele positivity and carriers having at least one of the risk allele was significantly higher than in counterparts with a GG wild genotype [ORGT/TT vs. GG: 1.73; 95% CI: 0.09-32; p = 0.03]. Yet, there was no evidence of an association between rs7574865 and autoimmune-related thyroid disease in psoriatic patients.

Conclusions

The STAT4 rs7574865 polymorphism increases autoimmune-related thyroid disease susceptibility among the general population but not in psoriatic patients.

Polymorphisms in STAT4 and IRF5 increase the risk of systemic sclerosis: a meta-analysis

BACKGROUND

Systemic sclerosis (SSc) is the most severe connective tissue disorder. Recent studies have demonstrated that genetic factors may play a role in the development of SSc. The aim of this study was to investigate the association of signal transducer and activator of transcription 4 (STAT4) rs7574865 and interferon regulatory factor 5 (IRF5) rs2004640 polymorphisms with risk of SSc.

METHODS

Case-control studies were obtained from the electronic database of PubMed, Medline, Embase, and CNKI (China National Knowledge Infrastructure) up to December 2013. The association between STAT4 and IRF5 polymorphisms and SSc susceptibility was assessed by pooled odds ratios (ORs) and 95% confidence intervals (CI).

RESULTS

Six related studies, including 4746 SSc cases and 7399 healthy controls, were pooled in this meta-analysis. For STAT4 polymorphism, we observed a statistically significant positive association between risk factor T allele carriers and SSc susceptibility (OR = 1.37, 95% CI = 1.27-1.48, P < 0.00001) in the overall population. The presence of limited cutaneous (lcSSc) and diffuse cutaneous (dcSSc) scleroderma also showed a significant association with each of the genetic models (P < 0.00001). For IRF5 polymorphism, the T allele was shown to be strongly associated with increased SSc risk (OR = 1.27, 95% CI = 1.17-1.39, P < 0.00001). No significant heterogeneity between studies was found.

CONCLUSIONS

The results demonstrated that STAT4 rs7574865 and IRF5 rs2004640G/T substitution are associated with a susceptibility to SSc, and they may serve as the SSc genetic susceptibility factor. These data confirmed that genetic polymorphisms may play a role in the development of SSc and have provided new insight into the pathogenesis of SSc.

Immunogenetics of juvenile idiopathic arthritis: A comprehensive review

Juvenile idiopathic arthritis (JIA) is the most common chronic inflammatory arthropathy of childhood. Juvenile idiopathic arthritis is believed to be a complex genetic trait influenced by both genetic and environmental factors. Twin and family studies suggest a substantial role for genetic factors in the predisposition to JIA. Describing the genetics is complicated by the heterogeneity of JIA; the International League of Associations for Rheumatology (ILAR) has defined seven categories of JIA based on distinct clinical and laboratory features. Utilizing a variety of techniques including candidate gene studies, the use of genotyping arrays such as Immunochip, and genome wide association studies (GWAS), both human leukocyte antigen (HLA) and non-HLA susceptibility loci associated with JIA have been described. Several of these polymorphisms (e.g. HLA class II, PTPN22, STAT4) are shared with other common autoimmune conditions; other novel polymorphisms that have been identified may be unique to JIA. Associations with oligoarticular and RF-negative polyarticular JIA are the best characterized. A strong association between HLA DRB1:11:03/04 and DRB1:08:01, and a protective effect of DRB1:15:01 have been described. HLA DPB1:02:01 has also been associated with oligoarticular and RF-negative polyarticular JIA. Besides PTPN22, STAT4 and PTPN2 variants, IL2, IL2RA, IL2RB, as well as IL6 and IL6R loci also harbor variants associated with oligoarticular and RF-negative polyarticular JIA. RF-positive polyarticular JIA is associated with many of the shared epitope encoding HLA DRB1 alleles, as well as PTPN22, STAT4 and TNFAIP3 variants. ERA is associated with HLA B27. Most other associations between JIA categories and HLA or non-HLA variants need confirmation. The formation of International Consortia to ascertain and analyze large cohorts of JIA categories, validation of reported findings in independent cohorts, and functional studies will enhance our understanding of the genetic underpinnings of JIA.

Pathogenesis of Systemic Sclerosis

Systemic scleroderma (SSc) is one of the most complex systemic autoimmune diseases. It targets the vasculature, connective tissue-producing cells (namely fibroblasts/myofibroblasts), and components of the innate and adaptive immune systems. Clinical and pathologic manifestations of SSc are the result of: (1) innate/adaptive immune system abnormalities leading to production of autoantibodies and cell-mediated autoimmunity, (2) microvascular endothelial cell/small vessel fibroproliferative vasculopathy, and (3) fibroblast dysfunction generating excessive accumulation of collagen and other matrix components in skin and internal organs. All three of these processes interact and affect each other. The disease is heterogeneous in its clinical presentation that likely reflects different genetic or triggering factor (i.e., infection or environmental toxin) influences on the immune system, vasculature, and connective tissue cells. The roles played by other ubiquitous molecular entities (such as lysophospholipids, endocannabinoids, and their diverse receptors and vitamin D) in influencing the immune system, vasculature, and connective tissue cells are just beginning to be realized and studied and may provide insights into new therapeutic approaches to treat SSc.

Association of PTPN22 rs2476601 and STAT4 rs7574865 polymorphisms with rheumatoid arthritis: A meta-analysis update

BACKGROUND

Rheumatoid arthritis (RA) is a common autoimmune disease with a complex genetic background. The genes encoding protein tyrosine phosphatase non-receptor type 22 (PTPN22) and signal transducer and activator of transcription 4 (STAT4) have been reported to be associated with RA in several ethnic populations.

OBJECTIVES

This work aims to assess the association between PTPN22 rs2476601 and STAT4 rs7574865 polymorphisms with RA susceptibility through an updated meta-analysis of available case-control studies.

METHODS

A literature search of all relevant studies published from January 2007 up to December 2014 was conducted using Pubmed and Science Direct databases. The observed studies that were related to an association between PTPN22 rs2476601 and STAT4 rs7574865 polymorphisms with RA susceptibility were identified. Meta-analysis of the pooled and stratified data was done and assessed using varied genetic models.

RESULTS

Thirty-seven case-control studies with a total of 47 comparisons (29 for PTPN22 rs2476601 polymorphism and 18 for STAT4 rs7574865 polymorphism) met our inclusion criteria. The meta-analysis showed an association between PTPN22 T allele, CT+TT and TT genotypes with RA susceptibility. Furthermore, The meta-analysis showed an association between STAT4 T allele, GT+TT and TT genotypes with RA susceptibility. Stratification of RA patients according to ethnic groups showed that PTPN22 T allele, CT+TT genotypes, STAT4 T allele and STAT4 GT+TT were significantly associated with RA in European, Asian, African subjects, while PTPN22 TT genotype was significantly associated with RA in European but not in Asian and African subjects and STAT4 TT genotype was significantly associated with RA in European and Asian but not in African subject. A subgroup analysis according to the presence or absence of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies revealed that the association between PTPN22 rs2476601 and STAT4 rs7574865 polymorphisms with RA susceptibility may not be dependent on RF and anti-CCP antibodies.

CONCLUSIONS

Our meta-analysis demonstrated that PTPN22 rs2476601 and STAT4 rs7574865 polymorphisms confers susceptibility to RA in total subjects and in major ethnic groups. The association may not be dependent on RF and anti-CCP antibodies.

Association between ankylosing spondylitis and the miR-146a and miR-499 polymorphisms

miRNAs are small, non-coding RNAs that regulate the expression of multiple target genes at the post-transcriptional level. Single-nucleotide polymorphisms (SNPs) in miRNA sequences may alter miRNA expression and have been implicated in the pathogenesis of multiple forms of arthritis, including rheumatoid arthritis (RA) and osteoarthritis. The present study explored the association between ankylosing spondylitis (AS) and two single nucleotide polymorphisms (SNPs), miR-146a rs2910164G>C and miR-499 rs3746444T>C, in a Han Chinese population. A case-control study consisting of 102 subjects with AS and 105 healthy controls was designed. The two miRNA SNPs were identified by direct sequencing. Subsequently, their gene and genotype frequencies were compared with healthy controls. A significant difference was observed in the miR-146a rs2910164G>C SNP. The frequency of the G allele was markedly higher in the AS patients than in the healthy controls (P = 0.005, Pc = 0.01, OR = 1.787), and the frequency of the GG genotype was higher in AS patients than in controls (P = 0.014, Pc = 0.042, OR = 2.516). However, no significant association was found between the miR-499 rs3746444T>C variant and susceptibility to AS. This is the first study to address the association between the miR-146a rs2910164G>C and miR-499 rs3746444T>C polymorphisms and AS, and it suggests a potential pathogenic factor for AS. Further studies are needed to validate our findings in a larger series, as well as in other ethnic backgrounds.

Signal transducer and activator of transcription 4 in liver diseases

STAT4 is a member of the signal transducer and activator of transcription (STAT) family of molecules that localizes to the cytoplasm. STAT4 regulates various genes expression as a transcription factor after it is phosphorylated, dimerizes and translocates to the nucleus. STAT4 activation is detected virtually in the liver of several mouse models of liver injury, as well as the human liver of chronic liver diseases. STAT4 gene polymorphism has been shown to be associated with the antiviral response in chronic hepatitis C and drug-induced liver injury (DILI), primary biliary cirrhosis (PBC), HCV-associated liver fibrosis and in hepatocellular carcinoma (HCC). However, the roles of STAT4 in the pathogeneses of liver diseases are still not understood entirely. This review summarizes the recent advances on the functional roles of STAT4 and its related cytokines in liver diseases, especially in regulating hepatic anti-viral responses, inflammation, proliferation, apoptosis and tumorigenesis. Targeting STAT4 signaling pathway might be a promising strategy in developing therapeutic approaches for treating hepatitis in order to prevent further injury like cirrhosis and liver cancer.

A multilocus genetic study in a cohort of Italian SLE patients confirms the association with STAT4 gene and describes a new association with HCP5 gene

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease with complex pathogenesis in which genes and environmental factors are involved. We aimed at analyzing previously identified loci associated with SLE or with other autoimmune and/or inflammatory disorders (STAT4, IL10, IL23R, IRAK1, PSORS1C1, HCP5, MIR146a, PTPN2, ERAP1, ATG16L1, IRGM) in a sample of Italian SLE patients in order to verify or confirm their possible involvement and relative contribution in the disease.

Materials and methods

Two hundred thirty-nine consecutive SLE patients and 278 matched healthy controls were enrolled. Study protocol included complete physical examination, and clinical and laboratory data collection. Nineteen polymorphisms were genotyped by allelic discrimination assays. A case-control association study and a genotype-phenotype correlation were performed.

Results

STAT4 was the most associated gene [P = 3×10⁻⁷, OR = 2.13 (95% CI: 1.59–2.85)]. IL10 confirmed its association with SLE [rs3024505: P = 0.02, OR = 1.52 (95% CI: 1.07–2.16)]. We describe a novel significant association between HCP5 locus and SLE susceptibility [rs3099844: P = 0.01, OR = 2.06 (95% CI: 1.18–3.6)]. The genotype/phenotype correlation analysis showed several associations including a higher risk to develop pericarditis with STAT4, and an association between HCP5 rs3099844 and anti-Ro/SSA antibodies.

Conclusions

STAT4 and IL10 confirm their association with SLE. We found that some SNPs in PSORS1C1, ATG16L1, IL23R, PTPN2 and MIR146a genes can determine particular disease phenotypes. HCP5 rs3099844 is associated with SLE and with anti-Ro/SSA. This polymorphism has been previously found associated with cardiac manifestations of SLE, a condition related with anti-Ro/SSA antibodies. Thus, our results may provide new insights into SLE pathogenesis.

STAT4 is required for IL-23 responsiveness in Th17 memory cells and NKT cells

STAT4 is a critical mediator of inflammatory immunity and is required for all known IL-12 biological responses, including the induction of IFN-γ and development of Th1 cells. We demonstrate that IL-23, an IL-12-related cytokine, also requires STAT4 for optimal IL-17 secretion from memory T helper cells and NKT cells. Although IL-23 stimulation had modest effects on STAT4 activation, STAT4-deficiency results in reduced Il23r expression. These data demonstrate a restricted requirement for STAT4 in innate and adaptive IL-17-secreting T cell responses that might contribute to inflammatory immunity.

Rheumatoid arthritis pathophysiology: update on emerging cytokine and cytokine-associated cell targets

Biologic therapies that target pathogenic cytokines such as TNF, IL-1β or IL-6 have greatly improved the treatment of RA. Unfortunately, not all RA patients respond to current biologic therapies and responses are not always maintained, suggesting that there are alternative drivers of RA pathogenesis that might serve as promising therapeutic targets. Discovery of the new Th17 subset of Th cells, and their role in autoimmune disease development, has implicated the proinflammatory IL-12 and IL-17 families of cytokines in RA disease pathogenesis. Members of these cytokine families are elevated in the blood and joints of RA patients and have been shown to remain elevated in patients who do not respond to current biologics. In addition, these cytokines have been shown to play roles in joint destruction and erosion. A new subclass of biologics that target the IL-12 and/or IL-17 signalling pathways are under development. Here we review evidence for a role of Th17 cells as well as IL-12 and IL-17 cytokines in RA pathogenesis as the rationale for a subsequent discussion of the ongoing and completed clinical trials of newly emerging biologic therapies directed at IL-12 or IL-17 pathway inhibition.

Rs7574865 polymorphism in signal transducers and activators of transcription 4 gene and rheumatoid arthritis: an updated meta-analysis of 28 case-control comparisons

OBJECTIVES

The objective of the present meta-analysis was to investigate whether the combined evidence shows an association between the STAT4 rs7574865 polymorphism and RA.

METHODS

A systematic search of all relevant studies published through April 2013 was conducted using MEDLINE, EMBASE, OVID, and ScienceDirect. The observational studies that were related to an association between the STAT4 rs7574865 polymorphism and RA were identified. The association between the STAT4 rs7574865 polymorphism and RA susceptibility was assessed using genetic models.

RESULTS

Seventeen case-control studies with a total of 28 comparisons (25 300 RA patients and 26 326 controls) met the inclusion criteria. A meta-analysis was conducted for genotype TT versus GT+GG, GT+TT versus GG, TT versus GG and T-allele. The meta-analysis showed an association between RA and the STAT4 rs7574865 TT genotype, GT+TT genotype and T-allele in all subjects. Stratification of RA patients according to ethnic group showed that the TT genotype, GT+TT genotype and T-allele were significantly associated with RA in Europeans, Asians, Africans and Latin Americans. A subgroup analysis according to the absence or presence of rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies revealed that the association between the STAT4 rs7574865 polymorphism and RA may be independent of the presence of RF and anti-CCP antibodies.

CONCLUSIONS

This meta-analysis demonstrated that the STAT4 rs7574865 polymorphism confers susceptibility to RA in major ethnic groups. The association may not be dependent on the presence of RF and anti-CCP antibodies.

Gene-gene interactions of IRF5, STAT4, IKZF1 and ETS1 in systemic lupus erythematosus

Interferon (IFN) activation signaling and T helper 17 (Th17)-cell/B-cell regulation play a critical role in the pathogenesis of systemic lupus erythematosus (SLE). Several studies have provided convincing evidence that polymorphisms in IRF5, STAT4, IKZF1 and ETS1 from these pathways may be involved in SLE by affecting gene expression or epistasis. We analyzed the genetic interaction in known SLE susceptibility loci from the four genes in northern Han Chinese. A total of 946 northern Han Chinese participated in this study (370 unrelated SLE patients and 576 healthy controls). Subjects underwent genotyping for the single-nucleotide polymorphisms (SNPs) rs2004640 in IRF5, rs7574865 in STAT4, rs4917014 in IKZF1 and rs1128334 in ETS1 by use of a TaqMan SNP genotyping assay and direct sequencing. Gene-gene interaction analysis involved direct counting, multifactor dimensionality reduction (MDR) and linear regression analysis. SLE patients and controls differed in allele frequencies of rs7574865, rs1128334 (P < 0.001) and rs4917014 (P < 0.01). Direct counting revealed that the frequency of risk homozygote combinations was higher for SLE patients than controls (P < 0.01). Furthermore, 2-, 3- and 4-way gene-gene epistasis in SLE was confirmed by parametric methods and MDR analysis. Gene expression analysis partially supported the findings. Our study confirmed the association of the IFN pathway or Th17/B-cells and the pathogenesis of SLE, and gene-gene interaction in this pathway may increase the risk of SLE.

Genetics of rheumatoid arthritis - a comprehensive review

The "Bermuda triangle" of genetics, environment and autoimmunity is involved in the pathogenesis of rheumatoid arthritis (RA). Various aspects of genetic contribution to the etiology, pathogenesis and outcome of RA are discussed in this review. The heritability of RA has been estimated to be about 60 %, while the contribution of HLA to heritability has been estimated to be 11-37 %. Apart from known shared epitope (SE) alleles, such as HLA-DRB1*01 and DRB1*04, other HLA alleles, such as HLA-DRB1*13 and DRB1*15 have been linked to RA susceptibility. A novel SE classification divides SE alleles into S1, S2, S3P and S3D groups, where primarily S2 and S3P groups have been associated with predisposition to seropositive RA. The most relevant non-HLA gene single nucleotide polymorphisms (SNPs) associated with RA include PTPN22, IL23R, TRAF1, CTLA4, IRF5, STAT4, CCR6, PADI4. Large genome-wide association studies (GWAS) have identified more than 30 loci involved in RA pathogenesis. HLA and some non-HLA genes may differentiate between anti-citrullinated protein antibody (ACPA) seropositive and seronegative RA. Genetic susceptibility has also been associated with environmental factors, primarily smoking. Some GWAS studies carried out in rodent models of arthritis have confirmed the role of human genes. For example, in the collagen-induced (CIA) and proteoglycan-induced arthritis (PgIA) models, two important loci - Pgia26/Cia5 and Pgia2/Cia2/Cia3, corresponding the human PTPN22/CD2 and TRAF1/C5 loci, respectively - have been identified. Finally, pharmacogenomics identified SNPs or multiple genetic signatures that may be associated with responses to traditional disease-modifying drugs and biologics.

Association between a C8orf13-BLK polymorphism and polymyositis/dermatomyositis in the Japanese population: an additive effect with STAT4 on disease susceptibility

Background

Accumulating evidence has shown that several non-HLA genes are involved in the susceptibility to polymyositis/dermatomyositis. This study aimed to investigate the involvement of C8orf13–BLK, one of the strongest candidate genes for autoimmune diseases, in susceptibility to polymyositis/dermatomyositis in the Japanese population. A possible gene–gene interaction between C8orf13–BLK and STAT4, which we recently showed to be associated with Japanese polymyositis/dermatomyositis, was also analyzed.

Methods

A single-nucleotide polymorphism in C8orf13–BLK (dbSNP ID: rs13277113) was investigated in the Japanese population using a TaqMan assay in 283 polymyositis patients, 194 dermatomyositis patients, and 656 control subjects.

Results

The C8orf13–BLK rs13277113A allele was associated with overall polymyositis/dermatomyositis (P<0.001, odds ratio [OR] 1.44, 95% confidence interval [CI] 1.19–1.73), as well as polymyositis (P = 0.011, OR 1.32, 95% CI 1.06–1.64) and dermatomyositis (P<0.001, OR 1.64, 95% CI 1.26–2.12). No association was observed between the C8orf13–BLK rs13277113A allele and either interstitial lung disease or anti-Jo-1 antibody positivity. The C8orf13–BLK rs13277113 A and STAT4 rs7574865 T alleles had an additive effect on polymyositis/dermatomyositis susceptibility. The strongest association was observed in dermatomyositis, with an OR of 3.07 (95% CI; 1.57–6.02) for the carriers of four risk alleles at the two SNP sites, namely, rs1327713 and rs7574865.

Conclusions

This study established C8orf13–BLK as a new genetic susceptibility factor for polymyositis/dermatomyositis. Both C8orf13–BLK and STAT4 exert additive effects on disease susceptibility. These observations suggested that C8orf13–BLK, in combination with STAT4, plays a pivotal role in creating genetic susceptibility to polymyositis/dermatomyositis in Japanese individuals.

Candidate genes for type 1 diabetes modulate pancreatic islet inflammation and β-cell apoptosis

Genome-wide association studies (GWAS) have identified more than 50 loci associated with genetic risk of type 1 diabetes (T1D). Several T1D candidate genes have been suggested or identified within these regions, but the molecular mechanisms by which they contribute to insulitis and β-cell destruction remain to be clarified. More than 60% of the T1D candidate genes are expressed in human pancreatic islets, suggesting that they contribute to T1D by regulating at least in part pathogenic mechanisms at the β-cell level. Recent studies by our group indicate that important genetically regulated pathways in β-cells include innate immunity and antiviral activity, involving RIG-like receptors (particularly MDA5) and regulators of type I IFNs (i.e. PTPN2 and USP18), and genes related to β-cell phenotype and susceptibility to pro-apoptotic stimuli (i.e. GLIS3). These observations reinforce the concept that the early pathogenesis of T1D is characterized by a dialogue between the immune system and pancreatic β-cells. This dialogue is probably influenced by polymorphisms in genes expressed at the β-cell and/or immune system level, leading to inadequate responses to environmental cues such as viral infections. Further studies are needed to clarify how these disease-associated variants affect pancreatic β-cell responses to inflammation and the subsequent triggering of autoimmune responses and progressive β-cell loss.

Association of STAT4 polymorphisms with susceptibility to type-1 autoimmune hepatitis in the Japanese population

Background/Aims

Recent studies demonstrated an association of STAT4 polymorphisms with autoimmune diseases including systemic lupus erythematosus and rheumatoid arthritis, indicating multiple autoimmune diseases share common susceptibility genes. We therefore investigated the influence of STAT4 polymorphisms on the susceptibility and phenotype of type-1 autoimmune hepatitis in a Japanese National Hospital Organization (NHO) AIH multicenter cohort study.

Methodology/Principal Findings

Genomic DNA from 460 individuals of Japanese origin including 230 patients with type-1 autoimmune hepatitis and 230 healthy controls was analyzed for two single nucleotide polymorphisms in the STAT4 gene (rs7574865, rs7582694). The STAT4 rs7574865T allele conferred risk for type-1 autoimmune hepatitis (OR = 1.61, 95% CI = 1.23–2.11; P = 0.001), and patients without accompanying autoimmune diseases exhibited an association with the rs7574865T allele (OR = 1.50, 95%CI = 1.13–1.99; P = 0.005). Detailed genotype-phenotype analysis of type-1 autoimmune hepatitis patients with (n = 44) or without liver cirrhosis (n = 186) demonstrated that rs7574865 was not associated with the development of liver cirrhosis and phenotype (biochemical data and the presence of auto-antibodies).

Conclusions/Significance

This is the first study to show a positive association between a STAT4 polymorphism and type-1 autoimmune hepatitis, suggesting that autoimmune hepatitis shares a gene commonly associated with risk for other autoimmune diseases.

Genetics in rheumatoid arthritis beyond HLA genes: what meta-analyses have shown?

OBJECTIVE

Rheumatoid arthritis (RA) is a complex disorder with many genetic and environmental factors to account for disease susceptibility. Individual genetic association studies usually suffer from small sample size leading to biased results of polymorphisms association with RA liability. Therefore, meta-analyses seem to resolve this limitation, up to a point, increasing the power of statistical analyses. In this review, we summarize the current knowledge of non-HLA genetic factors contributing to RA predisposition based on meta-analyses.

METHODS

Using the key words: rheumatoid arthritis, meta-analysis, and polymorphism, we searched the PubMed database for the associated articles. Up to the middle of November 2012, seventy-nine articles fulfilled the criteria and highlighted the current findings on the genetic factors contributing to RA susceptibility.

RESULTS

The association with RA was confirmed for 32 gene polymorphisms, being population specific in some cases. However, meta-analyses did not confirm an association in case of 16 gene variants, previously studied in individual studies for their association with RA.

CONCLUSIONS

The use of bioinformatics tools and functional studies of the summarized implicated genes in RA pathogenesis could shed light on the molecular pathways related to the disorder, helping to the development of new drug targets for a better treatment of RA.

Polymorphisms in JAK/STAT signaling pathway genes and risk of non-Hodgkin lymphoma

Impaired function of Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway genes leads to immunodeficiency and various hematopoietic disorders. We evaluated the association between genetic polymorphisms (SNPs) in 12 JAK/STAT pathway genes (JAK3, STAT1, STAT2, STAT3, STAT4, STAT5a, STAT5b, STAT6, SCOS1, SCOS2, SCOS3, and SCOS4) and NHL risk in a population-based case-control study of Connecticut women. We identified three SNPs in STAT3 (rs12949918 and rs6503695) and STAT4 (rs932169) associated with NHL risk after adjustment for multiple comparison. Our results suggest that genetic variation in JAK/STAT pathway genes may play a role in lymphomagenesis and warrants further investigation.

Replication study of STAT4 rs7574865 G/T polymorphism and risk of rheumatoid arthritis in a Chinese population

AIM

Rheumatoid arthritis (RA) and ankylosing spondylitis (AS) are common systemic autoimmune diseases with genetic and environmental predisposing factors. Signal transducer and activator of transcription 4 (STAT4) transmits signals induced by interleukin-12, interleukin-23 and interferon-γ, which are key cytokines and play important roles in the development of autoimmune diseases. Previous studies confirmed the STAT4 rs7574865 G/T locus to be associated with RA. Thus we conducted a replication study to investigate STAT4 rs7574865 G/T polymorphism and RA/AS susceptibility in a Chinese population.

METHODS

We studied STAT4 rs7574865 G/T gene polymorphism in 520 patients with RA, 100 AS patients and 520 controls in a Chinese population. Genotyping was done using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

RESULTS

When the STAT4 rs7574865 GG homozygote genotype was used as the reference group, the GT or GT/TT genotypes were associated with the risk for RA. After stratification analyses, a significantly increased risk for RA associated with the STAT4 rs7574865 GT genotype was evident among the rheumatoid factor (RF)-positive patients, patients with higher erythrocyte sedimentation rate (ESR) level and patients with higher RA disease activity score (DAS28) compared with the STAT4 rs7574865 GG genotype. A significantly increased risk for RA associated with the STAT4 rs7574865 TT genotype was evident among older patients and RF-negative patients compared with the STAT4 rs7574865 GG genotype. STAT4 rs7574865 G/T was not associated with susceptibility to AS.

CONCLUSION

This replication study confirmed that STAT4 rs7574865 G/T polymorphism was associated with the risk of RA.

CONDENSED ABSTRACT

STAT4 polymorphisms are associated with rheumatoid arthritis risk.