Human MHC class II molecules (HLA-DMB, HLA-DMA, HLA-DRA, HLA-DOA) in the top 30 DMRs, which could attract inflammatory tumour-specific CD4+ T cells and dampen CD8+ T cell antitumour reactivity (Donia et al., 2015), were found to be hypomethylated in all CLL patients in our study. Here, HLA-DOA is linked to B-cell chronic lymphocytic leukemia.