The asthma-associated region 17q12-q21 harbors three genes, the zona pellucida binding protein 2 (ZPBP2), gasdermin B (GSDMB) and ORM1-like 3 (ORMDL3), that show allele-specific differences in expression levels in lymphoblastoid cell lines (LCLs) and CD4+ T cells. Here, ORMDL3 is linked to asthma.