Finally, when analyzing DNA methylation changes in the peripheral blood of AUD subjects, we need to consider the proportion of different types of blood cells of each subject. Numerous studies have examined DNA methylation alterations in peripheral blood mononuclear cells (PBMCs, including T, NK, and B cells as well as monocytes) of patients with various diseases such as alcohol dependence.38 However, variations in DNA methylation profiles among different populations of PBMCs have also been reported.114 To examine AUD-associated blood DNA methylation changes, the proportions of different types of blood cells (eg, CD8T, CD4T, NK cells, B cells, monocytes, granulocytes, etc.) must be taken into consideration, as described in published studies.114,115
