IL17F rs763780 single nucleotide polymorphism is associated with asthma after bronchiolitis in infancy

Association of rs4711998 of IL-17A, rs2275913 of IL-17A and rs763780 IL-17F gene polymorphisms with non-segmental vitiligo in a Mexican population

Vitiligo is the most common depigmenting disease characterized by achromic macules due to selective loss of melanocytes. The pathogenesis remains poorly elucidated, and multiple hypotheses exist regarding its pathogenesis. Evidence suggests that stress on melanocytes can result in activation of the immune system, and involvement of both activated cluster of differentiation (CD8+) cytotoxic and CD4+ T cells in the dysfunction, depigmentation, and apoptosis of melanocytes. Recent studies show that the interleukin 17 (IL-17) axis plays a central role in the pathogenesis of the disease. IL-17 is an important regulatory effector cytokine in this pathway. The aim of this study was to evaluate the association of IL-17A rs4711998 (-832A/G), IL-17A rs2275913 (-197G/A), and IL-17F rs763780 (7488A/G) with vitiligo in a Northeastern Mexican population. This was a case-control study and included 116 patients with vitiligo and 116 control subjects. Genotype characterization of IL-17A rs4711998 (-832A/G), IL-17A rs2275913 (-197G/A), and IL-17F rs763780 (7488A/G) was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. A p ≤ 0.05 was considered significant. It was observed that the combination of the genotypes GG/GA for IL-17F rs763780 (7488A/G) was associated with an increased risk for the development of vitiligo (OR 2.0943, 95% Cl 1.2375-3.5445, p = 0.0056). Regarding IL-17A rs4711998 (-832A/G) and IL-17A rs2275913 (-197G/A) genotyping, no association with vitiligo development was found. In conclusion, the SNP rs763780 in the IL-17F gene appears to be a risk factor for vitiligo development in this Mexican population and it may be useful in future studies, especially for the development of new therapies.

Cumulative evidence for associations between genetic variants in interleukin 17 family gene and risk of human diseases

Background

Genetic association studies have elucidated the link of variants in the interleukin 17 (IL-17) family genes with susceptibility to human diseases, yet have obtained controversial outcomes. Therefore, we sought to update comprehensive synopsis of variants in the IL-17 family genes with susceptibility to human diseases.

Methods

Our study screened the Pubmed and Web of Science to enroll eligible articles and performed a meta-analysis, then graded the cumulative evidence of significant association using Venice criteria and false-positive report probability test, and finally assessed the function of variants with strong evidence.

Results

Seven variants in IL-17 family genes had significant relationships with susceptibility to 18 human diseases identified by meta-analyses. Strong evidence was assigned to 4 variants (IL-17A rs2275913, IL-17A rs8193037, IL-17F rs1889570, IL-17F rs763780) with susceptibility to 6 human diseases (lung and cervical cancer, spondyloarthritis, asthma, multiple sclerosis, rheumatoid arthritis), moderate to 2 variants with risk of 5 diseases, weak to 5 variants with risk of 10 diseases. Bioinformatics analysis suggested that the variants with strong evidence might fall in putative functional regions. Additionally, positive relationships for 5 variants with risk of 4 diseases (based on two datasets) and 14 variants with risk of 21 diseases (based on one dataset) were considered noteworthy.

Conclusions

This study offers updated and comprehensive clues that variants in the IL-17 family genes are significantly linked with susceptibility to cervical, lung cancer, asthma, multiple sclerosis, rheumatoid arthritis and spondyloarthritis, and elucidates the crucial role of the IL-17 regions in the genetic predisposition to cancer or noncancerous diseases.

IL17RA variations showed no associations with post-bronchiolitis asthma or lung function

BACKGROUND

Interleukin-17A (IL-17A) and IL-17F are involved in the pathogenesis of asthma and allergy. Interleukin-17 receptor A (IL-17RA), encoded by the IL17RA gene, is a common receptor for IL-17A and IL-17F. The aim of the present study was to evaluate the association of IL17RA gene variations with asthma, allergy, and lung function at school age in children prospectively followed up after hospitalization for bronchiolitis in early infancy.

METHODS

Data on IL17RA rs4819553, rs4819554, and rs4819558 polymorphisms and clinical outcomes, including asthma and allergic rhinitis, were available for 145 former bronchiolitis patients at 5-7 years and for 125 at 11-13 years of age. One hundred children underwent impulse oscillometry at 5-7 years and 84 underwent flow-volume spirometry at 11-13 years of age. The IL17RA rs4819553, rs4819554 and rs4819558 were completely co-segregating in Finnish children in our previous studies.

RESULTS

The distributions of the studied IL17RA wild versus variant genotypes and major versus minor allele frequencies did not differ between bronchiolitis cases and population controls. These variations showed no significant association with asthma or allergic rhinitis nor with lung function reduction at 5-7 or 11-13 years of ages. Only 5.6% to 6.4% of the variations were homozygous.

CONCLUSIONS

The IL17RA gene variations that were studied showed no association with susceptibility to severe bronchiolitis in infancy, nor with post-bronchiolitis asthma or lung function at school age. Future studies should evaluate other IL17RA polymorphisms and include more cases, and especially cases with homozygous variations.