Hybrid method Due to every method of gene transfer having shortcomings, there have been some hybrid methods
developed that combine two or more techniques. Virosomes are one example; they combine liposomes
with an inactivated HIV or influenza virus. This has been shown to have more efficient gene transfer in
respiratory epithelial cells than either viral or liposomal methods alone. Other methods involve mixing
other viral vectors with cationic lipids or hybridising viruses.