Experimental gene therapy silences hepatitis B by muting viral DNA

Researchers have reported an experimental therapy, CRMA-1001, that silences hepatitis B by adding methylation marks to the virus's DNA instead of attacking the virus directly. Current treatments rarely eliminate this viral DNA, letting infections rebound. The approach uses CRISPR-Cas9 as a 'locator' to find viral sequences and an 'effector' that switches them off while sparing the host's DNA.