Genetic variations in interleukin-12B in allergic rhinitis

Association of interleukin-12B rs6887695 with susceptibility to allergic rhinitis

Interleukin-12 (IL-12) is a heterodimeric cytokine encoded by two separate genes, IL12A and IL12B, which may play a regulatory role in allergen-induced inflammation through CD4⁺ T-cell subsets polarization. The aim of this study was to investigate the association of single-nucleotide polymorphisms (SNPs) in the IL12B gene with susceptibility to allergic rhinitis (AR). We performed a case-control study including 130 AR patients and 130 healthy controls to evaluate the possible association between IL12B gene SNPs (rs3212227, rs6887695) and the risk of AR using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Our results showed no significant association between IL12B rs3212227 A > C polymorphism with AR. In contrast, the GC genotype of rs6887695 G > C was associated with susceptibility to AR in comparison with the GG genotype (p = 0.049, OR = 1.684, 95% CI: 1.002-2.83). We also observed a statistically significant difference in the additive model (GC versus GG + CC, p = 0.03, OR = 1.705, 95% CI: 1.040-2.794) for SNPs rs6887695. Furthermore, haplotypes analysis demonstrated that C-C haplotype was associated with an increased risk of AR (p = 0.01, OR = 1.845, 95% CI: 1.114-3.057). Our findings suggest that IL12B rs6887695 polymorphism may be a potential biomarker for susceptibility to AR in an Iranian population.

Role of interleukins 12B and 17A genetic variation in house dust mites allergy

Background

The house dust mites (HDM) constitute a major cause of allergic diseases all over the world. Genes encoding interleukins 12B and 17A which determine the course of T cell-mediated immune response are prime candidates as allergic disease susceptibility. The purpose of this study was to evaluate whether a single-nucleotide polymorphisms (SNP) of interleukins 12B + 1188A/C (rs3212227) and 17A −197G/A (rs2275913) confers susceptibility to HDM allergic diseases. Through a case-control study, 120 subjects served as 60 dust mites' allergic patients and 60 healthy non-allergic controls. Total immunoglobulin (Ig) E level, eosinophilic count, serum interleukins 4, 10, 12B, and 17A levels for the studied subjects were measured. Then, genotyping of single-nucleotide polymorphisms (SNPs) at +1188A/C for IL12B and −197G/A for IL17A gene were conducted using restriction fragment length polymorphisms (RFLP-PCR).

Results

The present study showed that in HDMs' allergic subjects there was a significant increase in IL12B (+1188 A/C) and IL17A (−197 G/A) genotype variants compared to that of the controls. There was a significant increase in total IgE levels, eosinophil counts, and the levels of both IL-4 and IL-17A, while IL12B was significantly lower in patients compared to that of the controls. There was no significant difference in IL-10 levels between patients and controls.                                                                            

Conclusion

Our findings indicate that IL12B (+1188 A/C) and IL17A (−197G/A) might be associated with an increase in the susceptibility to dust mites’ allergic patients.

IL-12B Polymorphisms Are Associated with the Presence of Premature Coronary Artery Disease and with Cardiovascular Risk Factors: The Genetics of Atherosclerotic Disease Mexican Study

The aim of this study was to evaluate the association of the IL-12B polymorphisms with the presence of premature coronary artery disease (pCAD) and with cardiovascular risk factors. The study included 2163 individuals (1133 patients with pCAD and 1030 healthy controls). Seven IL-12B polymorphisms (rs1363670, rs3212220, rs3212227, rs6887695, rs1433048, rs2853694, and rs1368439) were determined by TaqMan assays. The associations were evaluated by logistic regression using inheritance models adjusted for confounding variables. The rs1363670 was associated with a low risk of pCAD (odds ratio [OR] 0.718, p_dominant = 0.034; OR 0.701, p_heterozygote = 0.024; OR 0.702, p_codominant1 = 0.025). The association of the polymorphisms with cardiovascular risk factors was evaluated independently in each group. In controls, the rs3212227, rs3212220, and rs6887695 polymorphisms were associated with subcutaneous abdominal fat > p75, whereas the rs6887695 was associated with a high risk of central obesity. In pCAD patients, the rs2853694 was associated with a low risk of insulin resistance; and association of rs3212227 and rs3212220 with a low risk of metabolic syndrome was found, and the rs6887695 polymorphism was nominally associated with a high risk of hyperuricemia. In conclusion, the IL-12B rs1363670 polymorphism was associated with a low risk of pCAD, and in both pCAD patients and healthy controls, some IL-12B polymorphisms were associated with cardiovascular risk factors.

Interferon-γ and interleukin-12 production in relation to gene polymorphisms in bacillus Calmette-Guérin osteitis

BACKGROUND

Interferon-γ (IFN-γ) and interleukin-12 (IL-12) play a crucial role in the defense against mycobacteria, and in the response to bacillus Calmette-Guérin (BCG) vaccination. We have previously reported clinical and outcome data of 222 BCG osteitis cases diagnosed in 1960-1988 in Finland. The immunological and genetic reports have been based on 132 blood samples obtained in 2007-2008.

METHODS

We compared IFNγ rs2430561 and rs35314021, IL12A rs568408 and rs2243115, and IL12B rs3212227 single-nucleotide polymorphisms (SNP) between 132 BCG osteitis patients and 99 population-based controls. In addition, stimulated production of IFN-γ and IL-12 in cell culture was evaluated in relation to the presence of IFNγ and IL12 wild versus variant genotypes, respectively.

RESULTS

The distributions of IFNγ rs2430561, IFNγ rs35314021, IL12A rs568408, IL12A rs2243115 and IL12B rs3212227 SNP did not differ between BCG osteitis patients and Finnish population-based controls. For IFNγ rs2430561, IFNγ rs35314021 and IL12A rs2243115, the negative result was confirmed by comparing the minor allele frequencies (MAF) in BCG osteitis cases with those in the publicly available genome aggregation database, including data for 3,472 Finnish persons. Instead, for IL12A rs568408 and IL12B rs3212227, the comparison of MAF in BCG osteitis cases with those in population-based and in aggregation-based controls gave conflicting results. The presence of the wild versus variant genotype had no significant association with IL-12 or IFN-γ production in BCG-stimulated cell cultures.

CONCLUSION

IFNγ gene polymorphisms did not show any association with BCG osteitis after newborn vaccination.

Genetic Variants in IL-12B and IL-27 in the Polish Patients with Systemic Lupus Erythematosus

To investigate the potential association between IL-12B and IL-27 gene polymorphisms and systemic lupus erythematosus (SLE), we performed a case-control study based on the Polish population. Patients with SLE and healthy individuals were examined for -6415 CTCTAA/GC (rs17860508) and +1188A/C (rs3212227) in IL-12B and -924A/G (rs153109) and 4730T/C (rs181206) in IL-27 gene polymorphisms using the high-resolution melting method, PCR-RFLP method and TaqMan SNP genotyping assay, respectively. An increased frequency of GC/GC genotype as well as GC allele of the IL-12B rs17860508 was found in patients with SLE, as compared with healthy subjects (P < 0.001). We did not find differences in genotype and allele frequencies of the IL-12B rs3212227 and IL-27 rs153109 and rs181206 variants between patients with SLE and controls. IL-27 haplotype rs181206C/rs153109G indicated higher risk for SLE (P = 0.002), whereas haplotype rs181206T/rs153109G indicated reduced risk for SLE (P = 0.005). The IL-12B rs3212227 A/C polymorphism was associated with the mean value of the platelets (PLT), urea and complement C3 level. Furthermore, IL-12B rs17860508 genetic variant showed correlation with PLT, prothrombin time, international normalized ratio and alkaline phosphatase. Our results revealed that IL-12B rs17860508 and IL-27 haplotype CG are genetic risk factors for SLE and that both IL-12B rs17860508 and rs3212227 predict disease phenotype.