Forkhead Box P3 Polymorphisms Research Articles

Association between FOXP3 polymorphisms and expression and neuromyelitis optica spectrum disorder risk in the Northern Chinese Han population.

Forkhead box P3 (FOXP3) plays a critical role in the pathogenesis of autoimmune disorders. In the present study, we genotyped three single-nucleotide polymorphisms, namely, rs2232365, rs3761548, and rs3761549, to determine the relationship between FOXP3 polymorphisms and neuromyelitis optica spectrum disorder (NMOSD) susceptibility among the Northern Chinese Han population. We genotyped single nucleotide polymorphisms at loci of the FOXP3 gene (rs2232365, rs3761548, and rs3761549136) in 136 NMOSD patients and 224 healthy subjects using the multiplex SNaPshot technique. Allele, genotype, and haplotype frequencies were compared. qPCR was used to analyze the mRNA expression levels of FOXP3 in the peripheral blood mononuclear cells of 63 NMOSD patients and 35 healthy subjects. Non-parametric tests were used to test the FOXP3 mRNA expression across the different groups. The minor allele frequency (MAF) of G in rs2232365 was markedly lower in the NMOSD group than in the control group (odds ratio [OR] = 0.57, 95% confidence interval [95% CI]: 0.41-0.79, p = 0.001). Using genetic (codominant, dominant, and recessive) models and performing haplotype analyses, the MAF of G in rs2232365 was shown to be associated with protection against NMOSD in this population. Furthermore, haplotype analysis revealed that the haplotype GCT and the rs2232365, rs3761548, and rs3761549 alleles predicted protection against NMOSD (OR = 0.63, 95% CI = 0.41-0.97, p = 0.038). The proportions of the three genotypes of rs2232365 (p = 0.001) were not significantly different between the moderate-to-severe (Expanded Disability Status Scale (EDSS) ≥ 3 points) and mild (EDSS < 3 points) groups. Evidently, the proportion of patients with the AA genotype (64.3%) among the rs2232365 patients was significantly greater in the moderate-to-severe group than in the mild group (36.4%). However, the proportion of patients with the GG genotype (15.2%) among the rs2232365 patients was significantly greater in the mild group than in the moderate-to-severe group (2.9%). The mRNA expression of FOXP3 was markedly greater in the NMOSD group than in the control group (p = 0.001). Nevertheless, acute non-treatment patients exhibited lower FOXP3 mRNA expression than healthy controls and patients in the remission group (p = 0.004 and 0.007, respectively). FOXP3 polymorphisms and haplotypes are related to NMOSD susceptibility among the Han Chinese population. The minor allele G of FOXP3 rs2232365 and the haplotype GCT are associated with protection against NMOSD. The GG genotype may decrease the severity of NMOSD, whereas the AA genotype is related to moderate-to-severe NMOSD. FOXP3 mRNA expression is greater in patients with NMOSD than in healthy controls. However, it is decreased in acute non-treatment patients compared with healthy controls.

The Role of FOXP3 Polymorphisms in Graves' Disease with or without Ophthalmopathy in a Turkish Population.

Forkhead box P3 (FOXP3) gene polymorphisms have been evaluated in many autoimmune diseases, including Graves' disease (GD), in different populations. However, those polymorphisms have not been analyzed in GD or Graves' ophthalmopathy (GO) in the Turkish population. In this study, we aimed to evaluate the frequency of FOXP3 polymorphisms in GD with or without ophthalmopathy in a Turkish population. The study included 100 patients with GO, 74 patients with GD without ophthalmopathy, and 100 age- and sex-matched healthy controls. In all study participants, rs3761547 (-3499 A/G), rs3761548 (-3279 C/A), and rs3761549 (-2383 C/T) single nucleotide polymorphisms (SNPs) were detected using the polymerase chain reaction-restriction fragment length polymorphism method. The chi-square test was used to evaluate genotype and allele frequencies. Odds ratios and 95% confidence intervals were calculated for genotype and allele risks. In the patient group (including GD with or without ophthalmopathy), the rs3761548 AC and AA genotype and rs3761549 CT genotype were significantly more frequent than in the control group (all p<0.05). No genotypic and allelic differences were observed for rs3761547 between the patient and control groups (all p>0.05). There was no statistically significant difference between the GO and GD without ophthalmopathy groups concerning the allele and genotype frequencies of all three FOXP3 SNPs (all p>0.05). The AC and AA genotypes of rs3761548 (-3279) and CT genotype of rs3761549 (-2383 C/T) were shown to be possible risk factors for GD development in the Turkish population. However, none of the three SNPs was shown to be associated with the development of GO in patients with GD.

Forkhead box P3 gene polymorphisms predispose to type 2 diabetes and diabetic nephropathy in the Han Chinese populations: a genetic-association and gender-based evaluation study

BackgroundFunctional mutations or polymorphisms affecting forkhead box P3 (FOXP3) can lead to their abnormal FOXP3 gene expression and/or defective Treg cells generation, thus resulting in autoimmune disease and inflammatory disorders. FOXP3 also plays a key role in Type 2 diabetes mellitus (T2DM) and its complications, because the disease usually involves chronic low-grade inflammatory disorders and is associated with long-term immune system imbalance. This study aimed to investigate the association between FOXP3 polymorphisms and the susceptibility to T2DM and type 2 diabetes nephropathy (T2DN) within the Han Chinese populations.MethodsPolymorphisms in rs3761548C/A and rs2294021C/T were examined in 400 patients (which include an equal number of T2DM and T2DN groups) and 200 healthy controls using PCR-HRM and sequence analysis.ResultsThe genotype and allelic frequencies of the two single nucleotide polymorphisms (SNPs) were significantly different in T2DM and the progression of diabetes developing to T2DN. The further gender-based evaluation showed that in female subjects, rs3761548C/A was associated with an approximately 3-fold higher threat for T2DM and 4.5-fold for T2DN, while there was no noticeable association with rs2294021C/T; in males, the promoter polymorphism showed an increased predisposition of 5.4-fold and 3.4-fold predisposition to T2DM and T2DN, respectively, while rs2294021 polymorphism could impart a nearly 2-fold risk of developing T2DN. An additional analysis of combined genotypes (rs3761548 C/A-rs2294021C/T) revealed that CC-CC and CC-CT can be considered protective combinations in the predisposition of males with diabetes towards T2DN, while AA-CC and AA-TT have the opposite effect.ConclusionsThis study demonstrated the possible involvement of individual and combined genetic associations of rs3761548C/A and rs2294021C/T polymorphisms with the susceptibility to diabetes and diabetic nephropathy in the Han Chinese population, as well as gender bias.

Human forkhead box protein 3 gene variants associated with altered susceptibility to idiopathic recurrent pregnancy loss: A retrospective case-control study.

The pathogenesis of recurrent pregnancy loss (RPL) is multifactorial and not completely elucidated. Dysregulated immunity was implicated with RPL, in which regulatory T cells (Tregs) are key. As Tregs development and function are regulated by forkhead box P3 (FOXP3) transcription factor, and as FOXP3 expression is genetically determined, a role for FOXP3 polymorphisms in RPL pathogenesis was suggested. To investigate the association of rs2294021, rs2232365, rs3761548, and rs141704699 FOXP3 variants with idiopathic RPL in Lebanese women. This retrospective case-control study included 386 RPL cases and 398 age-matched control women. Logistic odds ratios (OR) were estimated with 95% confidence interval after adjustment; a significance value of P<.05 was set. Significantly lower rs22944021 and rs2232365 minor allele frequency (MAF) was found in patients with idiopathic RPL in comparison with the control group. Furthermore, statistically significantly lower frequency of heterozygous and homozygous rs2294021 and rs2232365 genotypes was seen in controls, while significantly lower rs3761548 heterozygous genotype frequencies were found in the patient group. Obesity, antihypertension treatment, smoking, positive RPL family history, abortion state, and infertility treatment correlated negatively with rs2294021, while rs2232365 negatively correlated with obesity, and rs3761548 negatively correlated with infertility treatment. Marked linkage disequilibrium (LD) was noted among FOXP3 SNPs, with TGCC and CGAC haplotypes being positive, while CAAC, CACC, and TGAC haplotypes being negatively associated with RPL risk. Except for CGAC, the association of these haplotypes with RPL persisted after adjustment. FOXP3 gene variants and haplotypes are associated with altered incidence of RPL, proposing the role of Treg in RPL pathogenesis.

Assessment of the Relationship between Ulcerative Colitis and Forkhead Box P3 Polymorphisms.

Ulcerative colitis (UC) is a chronic disease that does not have a definitive treatment and causes repetitive inflammation of the colon and impaired quality of life. The FOXP3 gene codes FOXP3 protein responsible for development and function of regulatory T (Treg) cells. The rs2232365 A/G and the rs3761548 A/C polymorphisms of FOXP3 gene were indicated to be associated with inflammation-related diseases such as ulcerative colitis. The effectiveness of Treg cells, which act as immune-suppressors in the control of inflammation, can be affected by these polymorphisms. The aim of the present study was to evaluate the association between these polymorphisms with ulcerative colitis. The current study researched the FOXP3 gene polymorphisms in 146 patients with UC and in 292 healthy individuals by a real-time polymerase chain reaction (RT-PCR). The patients with rs2232365 G allele had a 1.44-fold higher UC risk than patients carrying other allele (P=0.013), and had significantly a 2.56-fold higher risk for extent of UC (P=0.001). Contrary, rs3761548 polymorphism didn't reach statistically significant in any analysis. This is the first study to reveal the relationship of the rs2232365 and the rs3761548 polymorphisms with ulcerative colitis in Caucasian population. The rs2232365 has an important effect on the risk of UC. The current study suggests that these polymorphisms should be explored together with the FOXP3 expression and FOXP3+ Treg cell count in blood and colon tissue of UC patients to clarify the exact effect of FOXP3 polymorphisms on UC risk.

Association of FOXP3 and GAGE10 promoter polymorphisms and decreased FOXP3 expression in regulatory T cells with susceptibility to generalized vitiligo in Gujarat population.

Alterations in regulatory T (Treg) cells have been observed in generalized vitiligo (GV) patients and decreased Forkhead Box P3 (FOXP3) has been implicated in the disease pathogenesis. The present study examined FOXP3 rs3761547(A>G), rs3761548(C>A), rs2232365(A>G) and GAGE10 rs11798415(A>T) promoter single nucleotide polymorphisms (SNPs) in 419 GV patients and 429 controls from Gujarat population using PCR-RFLP and ARMS-PCR. Real-time PCR and flow cytometry were used for assessment of FOXP3 mRNA and protein levels respectively in 96 GV patients and 90 controls. The frequency of genotypes (p<0.001) and alleles (p=0.012 & p=0.040) for rs3761547(A>G) and rs11798415(A>T) SNPs significantly differed between GV patients and controls. FOXP3 mRNA and protein levels were significantly decreased (p<0.001) in GV Tregs compared to controls. Active vitiligo (AV) Tregs showed significantly reduced FOXP3 mRNA and protein levels compared to that of stable vitiligo (SV) (p=0.02 & p=0.039). The correlation of genotype-phenotype of FOXP3 SNPs suggested reduced FOXP3 mRNA (p=0.019, p<0.001 & p<0.001) and protein (p=0.028, p<0.001 & p=0.022) levels in patients with susceptible GG, AA and GG genotypes respectively. The GAGT, GCGT & ACGT haplotypes were prevalent in GV patients (p=0.004, p=0.004 & p=0.016); however, GAGT & GCGT were overrepresented in patients with AV (p=0.044 & p=0.024). The susceptible GAGT and GCGT haplotypes in patients exhibited reduction in FOXP3 mRNA (p=0.014 & p=0.019) and protein (p=0.024 & p=0.028). DNA-protein docking analysis revealed reduced binding for transcription factor C/EBP to the susceptible allele 'G' (rs3761547) compared to A allele. For the first time, the study suggests significant association of FOXP3 rs3761547(A>G) & GAGE10 rs11798415(A>T) SNPs with susceptibility to GV in Gujarat population. In addition, the likely role of these SNPs in altered FOXP3 expression of Tregs may possibly affect Treg suppressive function in GV.

The association of FOXP3 gene polymorphisms with cancer susceptibility: a comprehensive systemic review and meta-analysis.

The role of forkhead box P3 (FOXP3) protein in tumorigenesis has long been controversial and existing data on the association between FOXP3 gene polymorphisms and cancer susceptibility were inconsistent. Here, we conducted a meta-analysis to better clarify the relationship. A comprehensive search of studies published from July 2008 to June 2018 was conducted. The statistical analyses of the pooled odds ratios (ORs) and the corresponding 95% confidence intervals (95% CIs) were performed using the Revman 5.2 software. A total of 12 articles with 19 case–control studies and 10389 participants were included. Three FOXP3 polymorphisms and six cancer types were evaluated. While no significant results were observed in overall and breast cancer groups for rs3761548 (A/C) polymorphisms, the pooled data showed an elevated risk of cancer in variant AA genotypes and A allele for Chinese population (AA vs. AC+CC: OR = 1.61, 95% CI = 1.09, 2.39; AA vs. CC: OR = 1.74, 95% CI = 1.05, 2.89; A vs. C: OR = 1.34, 95% CI = 1.00, 1.78). Neither the overall group analyses nor the subgroup analyses stratified by cancer type and ethnicity proposed any significant association of rs2280883 (C/T) and rs3761549 (T/C) polymorphisms with cancer susceptibility. This meta-analysis suggested that FOXP3 rs3761548 (A/C) polymorphisms were associated with increased cancer risk in Chinese population while rs2280883 (C/T) and rs3761549 (T/C) polymorphisms were not. More large-sample researches with diverse ethnicities and cancer types are needed to draw a concrete conclusion.

Association of Ulcerative Colitis with FOXP3 Gene Polymorphisms and Its Colonic Expression in Chinese Patients.

Abnormalities of forkhead box P3 (FOXP3) are implicated in various autoimmune diseases. This study is aimed at investigating the association of ulcerative colitis (UC) with FOXP3 polymorphisms and its colonic expression in Chinese patients. Polymorphisms of rs3761548, rs2232365, rs2294021, and rs3761547 were examined in 472 UC patients and 525 healthy controls using the SNaPshot method. The colonic expression of FOXP3 mRNA and protein was assayed in inflammatory mucosa of 34 UC patients and normal mucosa of 36 patients with benign sigmoid polyps (normal controls) using real-time quantitative polymerase chain reaction and immunohistochemical analysis. All data were handled separately for females and males. As a result, the carrier frequencies with at least one variant allele of rs3761548, rs2232365, and rs229402 increased in female and male UC patients compared with healthy controls. Significant differences in these carrier frequencies were also observed between patients with mild and moderate UC and patients with severe UC. The expression of FOXP3 was higher in UC patients (both males and females), especially those with severe UC, than in normal controls. The expression of FOXP3 was downregulated in UC patients having at least one variant allele compared with UC patients having no variant allele of rs3761548, rs2232365, and rs2294021. Male gender (β = −0.341), rs2294021 variation (β = −0.503), and severe UC (β = 0.361) were independently related to the mRNA expression of FOXP3 in UC patients. Together, our findings indicated that FOXP3 (rs3761548, rs2232365, and rs2294021) variations increased the risk of UC and were associated with the lower colonic expression of FOXP3 in UC patients.

Association of FOXP3 Single Nucleotide Polymorphisms With Clinical Outcomes After Allogenic Hematopoietic Stem Cell Transplantation.

BackgroundForkhead box P3 (FOXP3) is an important marker of regulatory T cells. FOXP3 polymorphisms are associated with autoimmune diseases, cancers, and allograft outcomes. We examined whether single nucleotide polymorphisms (SNPs) at the FOXP3 locus are associated with clinical outcomes after allogenic hematopoietic stem cell transplantation (HSCT).MethodsFive FOXP3 SNPs (rs5902434, rs3761549, rs3761548, rs2232365, and rs2280883) were analyzed by PCR-sequencing of 172 DNA samples from allogenic HSCT patients. We examined the relationship between each SNP and the occurrence of graft-versus-host disease (GVHD), post-HSCT infection, relapse, and patient survival.ResultsPatients with acute GVHD (grades II-IV) showed higher frequencies of the rs3761549 T/T genotype, rs5902434 ATT/ATT genotype, and rs2232365 G/G genotype than did patients without acute GVHD (P=0.017, odds ratio [OR]=5.3; P=0.031, OR=2.4; and P=0.023, OR=2.6, respectively). Multivariate analysis showed that the TT genotype of rs3761549 was an independent risk factor for occurrence of acute GVHD (P=0.032, hazard ratio=5.6). In contrast, the genotype frequencies of rs3761549 T/T, rs5902434 ATT/ATT, and rs2232365 G/G were lower in patients with post-HSCT infection than in patients without infection (P=0.026, P=0.046, and P=0.031, respectively).Conclusionsrs3761549, rs5902434, and rs2232365 are associated with an increased risk of acute GVHD and decreased risk of post-HSCT infection.

Association of two FOXP3 polymorphisms with breast cancer susceptibility in Chinese Han women.

BackgroundForkhead box P3 (FOXP3) is a key gene in the immune system which also plays a role in tumor development. This study aims to explore the association of two FOXP3 polymorphisms (rs3761548 and rs3761549) with susceptibility to breast cancer (BC).MethodA case–control study was conducted, involving 560 patients and 583 healthy individuals from the Chinese Han population. The genotypes of FOXP3 polymorphisms were detected using the Sequenom MassARRAY method. The association between FOXP3 polymorphisms and BC risk was evaluated using a χ2 test with an odds ratio (OR) and 95% confidence intervals (95% CIs) under six genetic models. False-positive report probability was utilized to examine whether the significant findings were noteworthy.ResultsWe observed that rs3761548 was associated with a higher BC risk in heterozygous, dominant, overdominant, and allele genetic models (CA vs CC: OR =1.32, P=0.031; CA/AA vs CC: OR =1.32, P=0.023; CA vs CC/AA: OR =1.29, P=0.042; A vs C: OR =1.26, P=0.029), whereas no significant association was found between rs3761549 and BC risk. In addition, CA, CA/AA genotype, and A allele of rs3761548 were related to larger tumor size, and the A allele was also correlated with a positive status of Her-2 in BC patients.ConclusionOur study suggests that FOXP3 polymorphism rs3761548 is associated with BC susceptibility in the Chinese and may be involved in tumor progression. Future studies are needed to confirm the results in a larger population with more races.

Association betweenFOXP3polymorphisms and vitiligo in a Han Chinese population

Vitiligo is an autoimmune chronic depigmentation disorder caused by melanocyte loss. Previous studies found that CD4(+)CD25(+) regulatory T-cell (Treg) dysfunction was involved in the pathogenesis of vitiligo and that gene polymorphisms in forkhead box P3 (FOXP3) - a master regulator of Treg development and function - were associated with susceptibility to some autoimmune disorders. Therefore, we hypothesized that functional polymorphisms of the FOXP3 gene might be associated with vitiligo via dysregulation of Treg cells. To evaluate whether FOXP3 polymorphisms are associated with vitiligo risk. In this hospital-based case-control study of 682 patients with vitiligo and 682 vitiligo-free age- and sex-matched controls, we genotyped three single nucleotide polymorphisms (SNPs) of the FOXP3 gene - rs2232365, rs3761548 and rs5902434 - by performing polymerase chain reaction with sequence-specific primers (PCR-SSP). Significantly increased vitiligo risk was associated with the rs2232365 GG [odds ratio (OR) 1·68, 95% confidence interval (CI) 1·17-2·39, P = 0·004] and rs3761548 AA (OR 1·82, 95% CI 1·10-3·01, P = 0·033) genotypes compared with the rs2232365 AA and rs3761548 CC genotypes. On combined analysis of these three variant alleles, we found that individuals carrying 2-6 variant alleles had significantly increased vitiligo risk (OR 1·34, 95% CI 1·08-1·66). This risk was more pronounced in the following subgroups: age > 20 years, male sex, active vitiligo, nonsegmental vitiligo and other accompanying autoimmune diseases. FOXP3 gene polymorphisms contributed to vitiligo risk in a Han Chinese population.