Genetic payload

The evolution of human food consumption happened alongside the development of a vast bacterial ecosystem resident within the human body this gut microbiome comprises a cargo of commensals and symbionts that has collectively evolved to survive in the distal part of the human intestine. This community of microorganisms is thought to harbour more than 100-fold the number of genes within the human genome (BSckhed et al 2004). This genetic payload is carried by an excess of lO microbial cells with over 1000 bacterial types (Wallace et al 2011) - the evolution of which probably happened in response to the particular diet available to humans at a particular time. 

DNA alone, or trapped inside a small fatty balloon that will melt into the cell s outer membrane, is also a possible vector. These vectors can carry large payloads, but because they do not include the viral genetic information, they are not very good at actually delivering the genetic material. 

---