Estimation of raw somatic mutations/Mb on control samples. (A) Raw somatic mutations/Mb on replicates of NA12878 (normal cell line), HCC1143 (breast cancer positive cell line), and custom AcroMetrix Hotspot Frequency Ladder containing engineered variants at 5%, 10%, 12.5%, 15%, 25%, and 50% frequency levels; (B) sensitivity and (C) specificity in detecting true, post-filter variants at different frequency levels.