In addition, in our sex-stratified analysis and at a p value ≤ 0.05, cg24735671 (TLR7, Δβ = 0.043) and cg20981403 (TLR8, Δβ = 0.036) showed differential DNA methylation by COVID-19 status only in males, whereas cg19782749 (HS6ST2, Δβ = 0.045) and cg00741717 (TLR8, Δβ = 0.042) were differentially methylated in females (Additional file 2: Fig. S7). Here, TLR8 is linked to COVID-19.