Resistance to Rabbit Haemorrhagic Disease (RHD) virus in wild Australian rabbits: comparison of susceptible and resistant individuals using a genome-wide approach. RHD Resistance in Australian Rabbits

The deciphering of the genes involved in disease resistance is essential if we are to understand host-pathogen co-evolutionary processes. The Rabbit Haemorrhagic Disease Virus (RHDV) was imported into Australia in 1995 as a biocontrol agent to manage one of the most successful and devastating invasive species, the European rabbit (Oryctolagus cuniculus). During the first disease outbreaks, RHDV caused mortality rates of up to 97% and reduced Australian rabbit numbers to very low levels. Recently, however, increased genetic resistance to RHDV and strong population growth has been reported. Here, we have aimed to identify genomic differences between rabbits that survived a natural infection with RHDV and those that have died in the field. We have chosen a genome-wide approach by using Next Generation Sequencing (NGS) and have identified 208 genes potentially associated with survival of an infection, several of them having known functions in viral infections. We have observed differences from experimental studies, highlighting the importance of field studies under natural selection regimes to infer the genomic background of wildlife diseases. We provide a set of candidate markers as a tool for the future scanning of wild rabbits for their resistance to RHDV. This is important both for wild rabbit populations in southern Europe where RHD is regarded as a serious problem decimating the prey of endangered predator species and for assessing the success of currently planned RHDV variant biocontrol releases in Australia.