HLA-DP allele analysis showed that DPA1*0201 and DPB1*0901, which were in strong linkage disequilibrium, were strongly associated with pediatric asthma (DPA1*0201: P = 5.5×10−10, OR = 1.52, and DPB1*0901: P = 2.0×10−7, OR = 1.49). The gene discussed is HLA-DPA1; the disease is asthma.