IL4R encodes a subunit of the interleukin-4 receptor, a molecule important for T-cell development and differentiation, and is a gene shown to be associated with immune-related diseases such as asthma and type I diabetes.
A significant interaction was found between R130Q in the IL-13 gene (IL13) and I50V in the IL-4 receptor alpha gene (IL4RA) on the risk of asthma, with a cross-validation consistency of 10 of 10 and a prediction error of 33.7% (P = .014).
A three-way gene-gene interaction was elucidated between the gene coding glutathione S-transferase P (GSTP1), the gene coding interleukin-4 receptor alpha chain (IL4Ra) and the gene coding insulin induced gene 2 (INSIG2) on the risk of lifetime asthma.
After subgroup analysis by age, the ACE D/I, β2-Adrenergic Receptor (β2-AR) -79G/C, TNF-α -308G/A, Interleukin 4 receptor(IL-4R) -1902G/A and IL-13 -1923C/T polymorphisms were found significantly associated with asthma risk in Chinese children.
Analysis of single markers showed the T-3223 IL4R allele to associate with lower serum levels of sIL-4 receptor (P<0.0001) and patients carrying the T allele also had more symptoms of active asthma (wheezing, P<0.01; coughing, P<0.05 and breathing difficulties, P<0.01).
Development of antagonistic antibody (Ab) against interleukin-4 receptor alpha (IL-4Rα) subunit of IL-4/IL-13 receptors is a promising therapeutic strategy for T helper 2 (T<sub>H</sub>2)-mediated allergic diseases such as asthma and atopic dermatitis.
Dupilumab (an anti-interleukin-4-receptor-α monoclonal antibody) blocks signalling of interleukin 4 and interleukin 13, type 2/Th2 cytokines implicated in numerous allergic diseases ranging from asthma to atopic dermatitis.
Dupilumab, a fully human monoclonal antibody targeting the interleukin-4 receptor α (IL-4Rα) subunit, demonstrated efficacy and acceptable safety in CRSwNP and other type 2 diseases (eg, atopic dermatitis and asthma).
Haplotype analysis showed a strong association between the IL4-34T/-589T haplotype and asthma per se (P=0.041), and a strong association between the IL4RA I50/Q576 haplotype and atopic asthma (P=0.006).
Immunologic studies suggest that IL4RA may interact with other cytokines and receptors, and gene-gene interactions have also been observed with respect to asthma.
In conclusion, our studies led to identification of some key candidate genes, namely IRF2, IL6, IFNGR2, STAT4 and IL4RA that modulate genetic susceptibility to asthma in the Indian population.
Individuals with CT and GG genotype of C1112T in IL 13 and Ile50Val in IL 4 R were at twice the risk for the development of asthma compared to individuals with both non-risk genotypes.