Figure 4.

Scatter plots showing the correlations between PER3 expression and sleep markers for each individual (represented by each dot). The mean fitted z-score peak (time in hours) of PER3 expression is plotted against (A) sleep onset (r = 0.48, P = 0.03), (B) wake time (r = 0.44, P = 0.055), (C) mid-sleep time (r = 0.49, P = 0.03), and the mean fitted z-score melatonin onset (D) (r = 0.59, P = 0.005) (all times in hours). Also shown are the correlations for melatonin onset against sleep time (E) (r = 0.78, P < 0.0001) and wake time (F) (r = 0.80, P < 0.0001).