Methylation is intricately linked to monocyte recruitment in COPD, as indicated by epigenetic networks that propose the involvement of the macrophage epigenetic factor protein arginine methyltransferase 7 (PRMT7) in the transcription and monomethylation of the RAP1A-regulated histone protein, which is crucial for monocyte recruitment 29,30. This evidence concerns the gene PRMT7 and chronic obstructive pulmonary disease.