Our findings on association of ADAR1p110 with RNase H2, but not with RNase H1 in living cells (Fig. 8a), together with elevated expression of RNase H2A subunit (Fig. 10a), especially at the M phase (Fig. 10c), further confirms collaboration between ADAR1p110 and RNase H2 in resolving specifically telomeric RNA:DNA hybrids containing A–C mismatches, perhaps at late G2 to M phase, in non-ALT cancer cells (Supplementary Fig. 10). Here, RNASEH1 is linked to cancer.