"DRB1*03 was positively associated with risk of asthma; DRB1*15 was negatively associated with risk of asthma; Subgroup analysis by age revealed that DRB1*03 DRB1*04 DRB1*09 and DRB1*15 were associated with asthma in children. Subgroup analysis by ethnicity showed that DRB1*03 and DRB1*15 were associated with asthma in whites and DRB1*07 and DRB1*14 were associated with asthma in Asians."xsd:string