Metagenomics and future perspectives in virus discovery

Area of Science:

• Virology
• Genomics
• Microbiology

Background:

• Traditional virus discovery relies on cell culture, limiting identification of unculturable viruses.
• Current virology has explored less than 1% of existing viral diversity.
• Metagenomic approaches offer culture-independent virus discovery.

Purpose of the Study:

• Review advances in viral metagenomics over the past decade.
• Highlight the relevance of viral metagenomics to virus discovery, clinical microbiology, and public health.
• Introduce the 'Metagenomic Koch's Postulates' for disease-associated virus identification.

Main Methods:

• Culture-independent and sequence-independent metagenomic analysis.
• Phylogenetic analysis of viral sequences.
• Review of recent viral metagenomic studies.

Main Results:

• Metagenomics has led to the discovery of numerous novel viruses, many phylogenetically distant from known ones.
• A significant portion (60-99%) of metagenomic sequences lack homology to known viruses.
• Metagenomics aids in characterizing normal viral populations and identifying potential zoonotic agents.

Conclusions:

• Viral metagenomics has revolutionized virus discovery, expanding our understanding of viral diversity.
• This approach is crucial for clinical microbiology, public health surveillance, and pandemic preparedness.
• The proposed 'Metagenomic Koch's Postulates' offer a new framework for linking viral traits to disease.