Fig. 1: Histogram of ERBB2 expression of samples colored by HER2 IHC scoring.
From: Enhancing HER2-low breast cancer detection with quantitative transcriptomics

a Histogram of samples profiled with RNA-Seq; b Histogram of samples profiled with microarrays. Distribution of HER2 IHC score is indicated in each bin by a different color; blue: 0; yellow: 1+; green: 2+/normal; orange:2+/amplified; pink: 3+. x-axis: normalized log2-transformed ERBB2 values measured with transcriptomics; y-axis: the number of samples in each bin.