ABSTRACT
Objective Childhood asthma is closely related to MP infection.This study was to investigate the distribution of ORMDL3 and HLA-DQ gene SNP in children with MP-associated asthma and gene-gene interactions.Methods One hundred and ninety-four patients with MP infection were enrolled.Extraction of whole blood genomic DNA was carried out.The genotype was collected by Flnidigm Juno 96.96 Genotyping integrated fluid pathway system.The patients were divided into MP-asthma group and MP-non-asthma group.Gene-gene interaction was analyzed by generalized multifactor dimensionality reduction.Results MP-asthma group included 63 cases (32.5％),MP-non asthma group included 131 cases (67.5％).ORMDL3 gene rs4794820 had three genotypes of AG,GG,AA.,MP-asthma group GG genotype and G allele frequency was higher than that in MP-non-asthma group.The frequency of AA genotype was the lowest among the two groups,but in the MP-non-asthma group were higher than that in the MP-asthma group.The rs7216389 had three genotypes of TT、TC、CC,the frequency of TT genotype and T allele in MP-asthma group was significantly higher than that in MP-non-asthma group.The frequency of CC genotype was the lowest among the two groups,but CC genotype in MP-non-asthma group was significantly higher than that in MP-asthma group.The rs794820 GG genotype and rs7216389 TT genotype were found to be risk factors.ORMDL3、HLA-DQA1 and HLA-DQA2 have gene-gene interaction.Conclusion MP infection is an important external cause of asthma in children.The genotype of rs7794820 GG genotype and rs7216389 TT genotype are an important internal cause of asthma after childhood MP infection.ORMDL3 rs4794820,rs7216389 and HLA-DQA1 rs9272346,HLADQA2 rs7773955 have gene-gene interaction,synergistically enhance the risk of asthma associated with asthma in children with MP.