Group I: Double-stranded DNA (dsDNA) viruses (e.g., Adenoviruses, Herpesviruses, Poxviruses).
Group II: Single-stranded DNA (ssDNA) viruses (e.g., Parvoviruses).
Group III: Double-stranded RNA (dsRNA) viruses (e.g., Reoviruses).
Group IV: Positive-sense single-stranded RNA (ssRNA) viruses (e.g., Picornaviruses, Togaviruses).
Group V: Negative-sense single-stranded RNA (ssRNA) viruses (e.g., Orthomyxoviruses, Rhabdoviruses).
Group VI: ssRNA viruses that use reverse transcriptase to replicate via a DNA intermediate (e.g., Retroviruses).
Group VII: dsDNA viruses that use reverse transcriptase to replicate via an RNA intermediate (e.g., Hepadnaviruses).