Renewing the virus taxonomy in the age of metagenomics

Project ID
NKFI NN 128309
Project leader
2018 - 2022

Nowadays, novel molecular techniques (metagenomics) make possible to get viral genome sequences from host organism or the environment even without the need for isolation of the virus on tissue cultures. This new approach started to yield an overwhelming number of presumed novel viruses and the virus taxonomy could not always keep up with their timely classification. We propose collaborative efforts to modernize and unify the virus classification process. Bioinformatics, semiautomatic methods will be applied to speed up the identification of novel candidate viruses and decide about their grouping in an existing virus species, or in a new candidate taxon if adequate divergence warrants it. Presently, the highest taxon level, accepted and applied in virus taxonomy is the order. We plan to establish and introduce more and higher taxon levels, comparable to those used for animals, plants, and other cellular organisms. We would like to make the first such examples for the animal DNA viruses and retroviruses. We also plan screenings to find novel DNA viruses in lower vertebrates and exotic animals that are relatively less studied. We expect to find “missing links” between certain known virus lineages. Data mining, i.e. screening databases for putative viral sequences, will also be performed to find unrecognized viruses. We would further clarify and fine-tune the genus demarcation criteria to determine more precisely what kind of characterisation and what level of difference is required between viruses for their separate classification. For the first time, the complete up-to-date virus taxonomy will be made freely available for everybody in form of well edited online chapters.