The illustration of the DMRs between humans and rhesus macaques from the Sequenom MassArray data. The CpG sites in the black rectangle are in a single CpG unit, and the methylation levels of each CpG site of the CpG unit is represented by the methylation level of that CpG unit. The CpG sites are numbered from 5' to 3' of the sequences of the PCR products on the measured DNA strands (Additional file 3). The CpG units that cannot be paired and not used in the study due to lacking of orthologous CpG units in the counterpart species are also shown in this figure. The 4 DMRs validated by the MassARRAY method are shown in A-D respectively. The region in blue rectangle is the MIR3 repeat element.