CD4 and cancer: Compared to large amount of histone modification mapping data that have been generated in the public databases, high-resolution nucleosome mapping has only been completed in a few human normal and cancer cell types, including CD4+ and CD8+ T-cells [8, 9], CD34+ hematopoietic stem cells and their derivatives, CD36+ erythroid lineage cells [10], IMR90 cells [11], human sperm [12, 13], human lymphoblastoid cell lines [14, 15], MCF7 [16], HEK293 [17], and K562 [15]; however, the qualities of these nucleosome mapping data varied and some data were from MNase digestion of crosslinked chromatin.