ABSTRACT
Objective To investigate the influences of interleukin 17A gene promoter -152G/A (IL-17A -152G/A) and interleukin 17F gene exon 7488 T/C (IL-17F 7488T/C) single nucleotide poly-morphisms on children bronchial asthma and serum total IgE ( TIgE) levels. Methods Genotype distribu-tion of IL-17A-152G/A and IL-17F 7488T/C in 224 children with asthma and 150 healthy subjects was de-tected by polymerase chain reaction-restriction fragment length polymorphism ( PCR-RFLP) analysis. Some samples were selected for PCR product sequencing and verification. IMMAGE800 specific protein analyzer from the Beckman Coulter test system was used to automatically detect serum TIgE levels in all subjects. Re-sults Three genotypes of AA, AG and GG were detected at IL-17A -152G/A locus in both asthma and control groups. Differences in genotype frequency distribution were statistically significant between the two groups (P<0. 05). Subjects carrying the variant allele A at IL-17A-152G/A locus were more likely to have asthma than those without (P<0. 05). Three genotypes of TT, TC and CC were detected at IL-17F 7488T/C locus in both asthma and control groups, but differences in the frequency distribution of genotype and al-lele were statistically significant between the two groups (P<0. 05). There was a significant difference in se-rum TIgE levels between asthma and control groups (P<0. 05). In asthma group, patients of AA genotype at IL-17A -152G/A locus had higher serum TIgE levels than those of AG genotype (P=0. 001) and GG geno-type (P=0. 001). No significant difference in serum TIgE levels was found among healthy subjects of the three genotypes in control group. No significant difference in serum TIgE levels was observed among the sub-jects of TT, TC and CC genotypes at IL-17F 7488T/C locus in asthma or control group (P>0. 05). Conclu-sion IL-17 gene polymorphism was correlated with the incidence of asthma in children in Guiyang area. IL-17A -152G/A polymorphism was an important candidate gene for asthma in Guiyang area and the variant al-lele A at -152G/A locus was correlated with increased serum TIgE levels. IL-17F 7488T/C polymorphism was also an important candidate gene for asthma in Guiyang. Children carrying the variant allele C at IL-17F 7488T/C locus showed a lower risk for asthma in Guiyang. IL-17F 7488T/C polymorphism had no influence on serum TIgE levels.