E. Proliferating H9-OCT4-mCherry hESCs were imaged for 24 h, fixed, and stained for DNA content with DAPI. The probability density of DAPI ratio (blue) and OCT4-mCherry ratio (red) between sister cells that divided ≤1 h prior to fixation was calculated for 151 cell pairs using a normal kernel function. A two-sample Kolmogorov-Smirnov test was used to determine significance. * P < 0.05, *** P < 0.0005, two-sample Kolmogorov-Smirnov test; ns, not significant. 