Two species of HIV infect humans: HIV-1 and HIV-2. HIV-1 is more virulent. It is easily transmitted and is the cause of the majority of HIV infections globally. HIV-2 is less transmittable and is largely confined to West Africa.
HIV1 and HIV2 have similar gag (viral core) and pol (polymerase) regions, they have relatively dissimilar env (envelope) regions. Owing to this lack of homology in the envelope region, there is little serologic cross-reactivity of the antibodies directed against the envelope antigens of both HIV1 and HIV2.
gp 32 is a form of truncated gp41; gp41 is formed from the envelope protein, gp160.
has not yet been referenced specifically in any publications.