Question

When two viruses with similar capsids co-infect a cell, it is possible for virions to be produced where the capsid does not match the genome. This phenomenon is known as phenotyphic mixing. What could be the conquences of this mismatch?

Answer 1

Phenotypic mixing is a biological phenomenon in which two viruses tend to share the similar capsid proteins, no matter what is the nature of their genetic material remains. According to this phenomenon, two virus particles co-infect a host. During infection, the viral particles disintegrate to release their capsid proteins. During replication, they again tend to restore their structure by binding to their capsid proteins. However, since the two different viral particles share the capsid proteins, there are 50% chances that these viral particles might switch from their original capsid protein to the alternative type. Hence, the external phenotypes of the viruses would be mixed, leading to phenotypic mixing.

Consequence: The pathological consequence of this phenomenon would be realised in anti-viral therapies which required the host-system to identify the capsid proteins to degrade the nucleic acids. Since the nucleic acids have already switched in this case, the host system would not be able to degrade it and hence infection would pursue leading to failure of anti-viral therapy.