Our ChIP experiments showed that H3K4me3 is present throughout the DEFB1 gene locus and, with exception of two positions within the promoter (region III) and exon 2 (region VIII), the levels of H3K4me3 correlate with transcriptional activity of DEFB1. Because H3K4me3 may well mark promoters and genes that became activated and provide the epigenetic setting to facilitate such activation [36], these results indicate that the establishment of such an active epigenetic code could be sufficient to establish the substantial induction of DEFB1 expression in the airways of COPD patients. The gene discussed is DEFB1; the disease is chronic obstructive pulmonary disease.