o Lentiviruses are a type of retrovirus that can integrate their genetic material into the host cell genome, enabling long-term expression. They can infect both dividing and non-dividing cells and have a larger cargo capacity than AAVs, accommodating full-size Cas9. However, their integration into the host genome raises concerns about insertional mutagenesis and oncogenesis. High transduction efficiency, larger cargo capacity (~8 kb), long-term expression, potential safety risks due to genome integration. o Adenoviruses are common viruses that cause mild infections in humans. They can deliver large DNA sequences and do not integrate into the host genome, which reduces the risk of insertional mutagenesis. However, they can elicit strong immune responses, which can be problematic for repeated treatments. Large cargo capacity (~8-10 kb), high efficiency, transient expression, potential for strong immune responses.