The HIV retrovirus, in particular, is a single-stranded RNA virus that duplicates itself in a host cell by converting its genetic code into double-stranded DNA that is then inserted into the host cell.

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The polymerase helps the virus churn out millions of copies of its RNA genetic material.

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In this research the scientists created a synthetic viral shell, but lacking its pathogenic RNA interior - the genetic material the virus uses to replicate itself.

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This is despite the fact that deleting the SOR gene makes it impossible for the virus to replicate and would permit use of virtually all of the AIDS RNA to be used in the vaccine, minus the SOR gene.

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