CHEK2 and cancer: The median LST and tAI counts in cancers from individuals heterozygous for CHEK2 gPVs were 4 (range = 0-16) and 8.5 (range = 0-26), respectively, which is comparable to the counts observed in our CHEK2-deficient cancers (Figure 1, A and B; Supplementary Figure 2, available online).