Supplementary Figure 9: Detection limit of rare subpopulations.
From: Single-cell ChIP-seq reveals cell subpopulations defined by chromatin state
In-silico subsampling of data to simulate lowering the size and frequency of ES and MEF subpopulations derived from H3K4me2 data. The fraction of cells from the subsampled clusters that were correctly classified (True Positives) is plotted for ES1 (A) and for MEF (B) as a function of relative cluster size (Frequency) and of the total number of cells in the in-silico sample. C) True positive rate (color coded) averaged over all ES clusters is plotted as a function of the frequency and size of the targeted subpopulation. The contour line of True Positives = 75% is fitted by a model (white line) that predicts that to maintain a given purity of clustering the size of the subpopulation should grow inversely proportional with the frequency of the subpopulation. D) The model used in C predicts that the number of cells required for accurately detecting a subpopulation grows quadratically for rare subpopulations. This prediction was numerically validated by subsampling our data for populations of up to 5000 cells and for subpopulations as rare as 3% (dashed lines).
