It is a trimer of identical heterodimer that is composed of a surface subunit (gp120) and a transmembrane subunit (gp41).3 Although HIV-1 infection can give rise to an antibody response against most viral proteins, only those antibodies binding to Env are able to neutralize the virus.4 The exposed surface of Env is coated by N-linked glycans, which shield the Env protein from recognition by the immune system. This evidence concerns the gene ERVW-1 and HIV-1 infection.