Farewell to smallpox virus?

[Anne Savitt]

Re: Farewell to smallpox virus?

I could not find the exact size of the variola genome, but the vaccinia
genome consists of 140,000 bases and encodes in excess of 100 proteins. 
Vaccinia is considered the prototypical poxvirus, and is thought to be a
derivative of cowpox virus.  It was the basis for the vaccine which
eradicated smallpox.  The variola genome is probably approximately the
same size.

This size makes it highly unlikely that anyone would reconstruct the
smallpox genome to try and make an infectious particle.  This is, of
course, complicated by the fact that the DNA itself is probably not
infective, and in the absence of the virion proteins, would not be able
to enter a cell to begin a replication cycle.  Then again, why would you
want to recreate an infectious particle?  Since the entire genome has
been sequenced and published, any information it contains is available
for the asking.  It would certainly not be impossible to genetically
engineer any protein which might be important, or characterize any
control regions, etc.  

Anne Savitt
Department of Microbiology
SUNY Stony Brook
Stony Brook, NY   11794
email:  asavitt at sunysb.edu