Association Of Interleukin-17A And-17F Gene Polymorphisms And Susceptibility Of Asthma In Chinese Middle-area Han Population

Part Ⅰ Interleukin-17 A and-17 F gene polymorphisms associate with susceptibility of asthmaObjective: In this study, we examined three SNPs of IL-17 gene(rs3748067, rs763780 and rs2397084) in Chinese asthma patients. We also evaluated the association of genotypes and allele frequencies between asthma patients and healthy controls.Methods: The genotypes were explored by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) method in 221 Asthma patients and 223 healthy controls(HC). Genotype distribution and allele frequency were analyzed statistically.Results: The frequency of rs3748067 A allele, GA and(GA+AA) were significantly higher in asthma patients than in HC(10.86% vs 4.26%, P <0.001; 19.91% vs 7.62%, P =0.001;20.81% vs 8.07%, P <0.001). As for rs763780, the allele "C" in patients was more frequent than in HC. Besides, we found C carriers(CT+CC) were significantly higher in the asthma than the controls(30.77% vs 21.97%, P = 0.035). Additionally, there was no significant association observed for rs2397084. The haplotype CT(rs763780/rs2397084) of IL-17 F was significantly associated with an increased susceptibility of asthma, especially in females.(19.5% vs 11.4%, OR = 1.899, 95% CI 1.121–3.215).Conclusions: Our findings indicated that IL-17 gene polymorphisms and haplotypes in promoter were associated with the susceptibility to asthma in Chinese Han population. These findings could be helpful in identifying individuals in a higher risk of asthma and further studies are warranted to validate them.Part Ⅱ Interleukin-17 gene polymorphisms associate with serum Ig E levelsObjective: In this study, we examined three SNPs of IL-17 gene(rs3748067, rs763780 and rs2397084) in Chinese asthma patients. We also evaluated the association of genotypes and alleles frequencies between asthma patients and healthy controls, and the association with Ig E.Methods: The genotypes were explored by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) method in 221 Asthma patients and 223 healthy controls(HC). Genotype distribution and allele frequency were analyzed statistically.Total serum Ig E levels were detected by direct Chemiluminescent method. Then compared them among different genetypes in asthma patientsResults: The serum Ig E levels of 221 asthma group samples were significantly higher than samples of 223 control group(577.338 IU/m L 46.521 IU/m L, P < 0.001). The risk factor of rs3748067 GA + AA was more pronounced in patients with higher serum total Ig E levels(OR:5.011[1.454~17.266]、P=0.005). No obvious correlation in SNP of rs3748067 and Ig E of the control group had been found. But it is worth noting that SNP of rs3748067 and serum total Ig E of asthma group showed a high correlation. The serum total Ig E of rs3748067(GA + AA) were significantly higher in asthma patients than in controlsConclusions: Our findings indicated that genetypes of rs3748067 GA +AA were more pronounced in patients with higher serum total Ig E levels and rs3748067 GA and AA in asthma patients from Chinese Han population were associated with the serum total Ig E. These findings could be helpful in identifying individuals in a higher risk of asthma and further studies are warranted to validate them.