Age-related HCP5 DNA methylation was associated with gene expression in human monocytes and T cells [121], and the expressed genes that linked to potentially functional age-related methylation sites were enriched with antigen processing and presentation MHC class I and class II genes that were implicated in ‘parainflammation’ and the development of age-related chronic inflammatory diseases and autoimmune diseases. This evidence concerns the gene HCP5 and autoimmune disease.