AQR and gastric cancer: In particular, the genes encoding RNase H2 and the RNA/DNA helicase Aquarius (AQR), and genes encoding the components of the TREX-2 mRNA export complex—all known to be involved in R-loop processing or prevention45,51,60,70 were recurrently subjected to CNVs or mutated in gastric cancer, and especially in the microsatellite instable and chromosomally instable subtypes of the disease.