DNA viruses belong to either Group I or Group II of the Baltimore classification system for viruses.

Although Group VII viruses such as hepatitis B contain a DNA genome, they are not considered DNA viruses according to the Baltimore classification, but rather reverse transcribing viruses because they replicate through an RNA intermediate.

The ICTV classifies RNA viruses as those that belong to Group III, Group IV or Group V of the Baltimore classification system of classifying viruses, and does not consider viruses with DNA intermediates in their life cycle as RNA viruses.

Viruses with RNA as their genetic material but which include DNA intermediates in their replication cycle are called retroviruses, and comprise Group VI of the Baltimore classification.

Animal RNA viruses are classified into three distinct groups depending on their genome and mode of replication ( and the numerical groups based on the older Baltimore classification ):

Currently there are two main schemes used for the classification of viruses: the ICTV system and Baltimore classification system, which places viruses into one of seven groups.

Baltimore classification ( first defined in 1971 ) is a classification system that places viruses into one of seven groups depending on a combination of their nucleic acid ( DNA or RNA ), strandedness ( single-stranded or double-stranded ), Sense, and method of replication.

* The dsRNA virusses ( e. g. Rotavirus ) according to the Baltimore classification.

* Baltimore classification, system used to classify viruses, named for biologist David Baltimore

They are classified as group I under the Baltimore classification scheme, meaning their genomes consist of double stranded DNA.

Mimivirus has been placed into a viral family by the International Committee on Taxonomy of Viruses as a member of the Mimiviridae, and has been placed into Group I of the Baltimore classification system.

In 2004, a group of international uveitis specialists convened in Baltimore, MD, to standardize the method of reporting data in uveitis clinical trials, including anatomical classification.

The Aberdeen IronBirds are a Short-Season A classification affiliate of the Baltimore Orioles.

According to the Baltimore classification they are considered class II viruses.

The Birnaviridae are type-III viruses in the Baltimore classification, which means they have a double-stranded RNA genome.

The viruses are positive-sense ssRNA viruses, placing them in Group IV of the Baltimore classification.

The Togaviridae family belong to group IV of the Baltimore classification of viruses.

Viruses in this family are classified as Type IV viruses in the Baltimore classification, and are part of the luteovirus supergroup.

It has a negative sense single stranded RNA ( ssRNA ) genome, and so is classified as a class V virus under the Baltimore classification system.

Under the Baltimore classification scheme, the Caudovirales are group I viruses as they have double stranded DNA ( dsDNA ) genomes, which can be anywhere from 18, 000 base pairs to 500, 000 base pairs in length.

In biology and immunology, an alphavirus belongs to the group IV Togaviridae family of viruses, according to the system of classification based on viral genome composition introduced by David Baltimore in 1971.