'Epigenetic' editing is here: gene-tagging technique banishes hepatitis B virus

Researchers report that epigenetic editing — attaching chemical methyl tags to DNA rather than cutting it — can durably silence hepatitis B virus genomes hiding inside liver cells, without introducing breaks in the host genome. Chronic hepatitis B infection is one of the leading causes of hepatocellular carcinoma worldwide, so permanently shutting down persistent viral DNA could lower long-term liver-cancer risk in the roughly 250 million people living with the infection. The same tag-based silencing platform is being explored for switching off cancer-driving genes, making this a proof of concept for a broader therapeutic toolkit. The work remains at an early translational stage, with clinical efficacy and durability in patients still to be demonstrated.