The project aims to study the features of the Hepetitis E Virus (HEV) genome which permits replication between species. HEV has eight genotypes however we are interested in the differences between genotype 1 and genotype 3. Genotype 1 is an obligate human pathogen meaning it is only capable of human transmission, primarily via the fecal-oral route. Genotype 3 is zoonotic and commonly infects deer, pigs and wild boar. It is typically transmitted to humans through infected meat. Using viral and replicon systems we will utilise saturating mutagenesis within the hypervariable region (HVR) of the HEV genome. We can then insert the replicon RNA into human and porcine cells and compare the replication abilities using fluorescence tagging and live cell imaging. These efforts will initially focus on Genotype 3 as the literature suggests Genotype 1 is not replication competent in porcine cell lines. However, once controls are established, there is scope to mutate and compare the HVR of Genotype 1 to establish which areas permit cross species replication of HEV and related viruses.