In a parallel fashion, it is possible that OCT-1 coordinates with CTCF to direct IL33 expression at the locus through creation of appropriate chromatin interactions between the 5 kb asthma-associated region and the IL33 promoter, which might explain the loss of E2-Crimson expression observed in hIL33CrimBAC5kdel mice (Fig. 2b–d). This evidence concerns the gene CTCF and asthma.