6.2.4 Classification

Question 1

What is the classification of viruses related to?

Answer 1

• to genetic characteristics of the virus itself, not classified in terms of what disease they cause or what type of animal they infect

Question 2

How does the Baltimore classification work?

Answer 2

Divides all viruses into seven groups according to mechanism of replication and type of nucleic acid present:

-group 1: dsDNA
-group 2: ssDNA
-group 3: dsRNA
-group 4: ssRNA (+ve sense)
-group 5: ssRNA (-ve sense)
-group 6: ssRNA (+ve sense, reverse transcribing)
-group 7: dsDNA (reverse transcribing)

Question 3

What does ICTV stand for?

Answer 3

International Committee for Taxonomy of Viruses

Question 4

What do we mean by positive/ negative sense?

Answer 4

The RNA strand that is messenger sense (translated by the ribosome) is positive sense.