Liver diseases, including cancer, are treated using dSaCas9-KRAB and dCas9-cre-CRISPRa systems, which target genes like Pcsk9 and proto-oncogenes, offering advances in cholesterol management and cancer genetics (Thakore et al., 2018; Wang et al., 2018a; Wangensteen et al., 2018). The gene discussed is PCSK9; the disease is cancer.