Analysis of Polymorphisms in Olive Pollen Allergy: <i>IL13, IL4RA, IL5 </i>and <i>ADRB2</i> Genes

Abstract

Background: Previous results demonstrated that sensitization to specific olive pollen allergens could be related with a different clinical pattern (asthma and/or rhinitis), and that specific patterns of sensitization are regulated by different HLA class II antigens. The authors analyze the possible implication of 7 genetic polymorphisms described as asthma susceptibility genes: IL13 (C–1112T and R130Q), IL4RA (I50V, Q551R), IL5 (C–746T) and ADRB2 (Q27E and R16G) in specific olive pollen allergic sensitization. Methods: The authors genotyped seven polymorphisms of the IL13, IL4RA, IL5 and ADRB2 genes in 146 patients allergic to olive pollen with seasonal rhinitis/asthma and 50 controls using the polymerase chain reaction-restriction fragment length polymorphism and real-time polymerase chain reaction techniques. Results: Two polymorphisms of IL13 were associated with allergy to olive pollen: the TT genotype of IL13 C–1112T was decreased (odds ratio, OR = 0.35, p = 0.006) whereas the RQ heterozygous genotype of IL13 R130Q increased in patients allergic to olive pollen (OR = 3.12, p = 0.009). The combined analysis of two IL4RA single nucleotide polymorphisms (SNPs) (I50V and Q551R) showed an association with asthma: IL4RA V50/Q551 was associated with risk (OR = 2.48, p = 0.007) whereas the IL4RA V50R551 haplotype was associated with protection (OR = 0.31, p = 0.003). Conclusions: The IL13 polymorphisms under study were associated with specific allergy to olive pollen: the IL13 C–1112T polymorphism as a protective factor and the IL13 R130Q polymorphism as a risk factor. Interestingly, although single polymorphisms of IL4RA are not associated with any phenotype analyzed, the interaction between IL4RA I50V/Q551R was strongly associated with the asthma phenotype. IL13 and IL4RA could be relevant markers for allergy to olive pollen and asthma development.

Interleukin 13 and Interleukin 4 Receptor-α Polymorphisms in Rhinitis and Asthma

“…Our results thus indicate that, due to the high coexistence of asthma and rhinitis, previous genetic studies on rhinitis may have been confounded by the presence of asthma. Notwithstanding this, other studies did report similar findings showing associations of IL13 and IL4R polymorphisms with cedar pollinosis [17], nonatopic rhinitis [18], self-reported medical diagnosis of hay fever [19], and allergic rhinitis [20,21]. These results are strengthened by our findings.…”

Identification of IL13 C1923T as a Single Nucleotide Polymorphism for Asthma in Children from Mauritius

“…Polymorphisms within IL-13 genes have been associated with the development of asthma in populations from Korea, 22 the UK, 23 and Spain. 24 This study did not find a significant difference in IL13 C1923T TT between the experimental and control group. Wu et al suggested that the T allele of the IL-13 C1923T was significantly associated with an increased risk of asthma in pediatric asthma patients in Middle rs569108 C____900116_10 rs1441586 C___1842226_10 rs1042713 C___2084764_20 rs1801275 C___2351160_20 rs1805010 C___2769554_10 rs2243250 C__16176216_10 rs20541 C___2259921_20 rs1295686 C___8932053_10 rs1800925 C___8932056_10 rs4950928 C__27832042_10 SNP, single nucleotide polymorphism.…”

FOXP3 and TGF-β: Differential Regulatory Molecules between Sensitization and Tolerance to Olive Pollen

“…Our patients were from Andalusia, a region in southern Spain with particularly high pollen counts during the pollen season (5,000 grains/m' with peaks reaching more than 10,000 grains/m-) and a high prevalence of asthma (15). We previously described specific genetic and environmental factors associated with olive pollen allergy (16)(17)(18)(19)(20). The interesting point of our study is that it was carried out in an area with unusually high antigenic load, where it had been previously demonstrated that patients had specific genetic restrictions and clinical symptoms depending on the nature of olive allergen implicated in sensitization (IS-19).…”