CYP1A1 and susceptibility to pneumonia measurement: IMP-mediated DEGs showed significant enrichment in pathways related to “cytochrome P450,” “tyrosine metabolism,” “retinoic acid metabolic process,” “biological oxidations,” and “pneumonia.” Notably, among the DEGs associated with these pathways, the CYP1A1, CYP1B1, AHRR, and ALDH3A1 genes were markedly upregulated by IMP (Fig. 1F–I).