CLOCK and breast carcinoma: Interestingly, the fCpG sites in the clock set were more tightly concentrated around β=0.5 in normal breast tissue, as compared to breast cancers (Fig. 2E), with a median standard deviation of β-values in normal samples of 0.09, compared to 0.21 in tumors (P = 2×10−45, Wilcoxon rank sum test).