F8 and hemophilia A: An example of this is the experiment performed by Chen et al. in which a Staphylococcus aureus Cas 9-guide RNA (SaCas9-gRNA), targeting the albumin (Alb) locus in liver cells DNA, and a codon-optimized human B domain deleted-FVIII (BDD-FVIII) were administered separately in haemophilia A mice models using adeno-associated virus (AAV) vectors (20).