Figure 1: Development and assessment of the MSI NGS caller. (A) Principle component analysis was used to visualize separation of 94 MSS, MSI-H and normal training cases that were run by MSI-PCR and MSI NGS. (B) 11 out of 24 samples with MSI-PCR data fell between a ±3 centroid distance between cluster 1 and 3. Four had discordant MSI-PCR and MSI NGS calls (black). The inconclusive range was set at > -3 to < 3 (dashed lines). (C and D) The average number of peaks identified in MSI-H, MSS and normal samples by MSI NGS and MSI-PCR for the two shared Bethesda markers.