I am aware that many studies use DMR to measure methylation level / region. However, DNA methylation impose its impact by suppressing gene expression. When we try to measure the magnitude / consequence of DNA methylation, should not we consider more about the correlation between methylation and mRNA expression (things like whether different CpG site have equal contribution on the expression of corresponding gene?) than merely defining statistically methylated region? I am a bit doubtful regarding the biological validity of DMR. Can anyone share some comment on this?