The methylation of IRF7 is associated with SSc, among the methylation status of 16 CpG sites at the promoter region of the IRF7 gene, CpG2 is significantly hypomethylated in SSc PBMCs and associated with increased disease risk, a significant difference in IRF7 mRNA expression between CpG8 methylated and unmethylated SSc patients, with four times higher in those who had a methylated CpG8 site than an unmethylated site (43). Here, IRF7 is linked to systemic sclerosis.