ERVW-1 and HIV-1 infection: The level of IgG antibodies (Abs) binding to a fusion protein consisting of the first and second variable regions (V1V2) of an HIV-1 gp120 envelope glycoprotein and the gp70 of murine leukemia virus [2] was identified as a statistically significant inverse correlate of risk (CoR) of HIV-1 infection [3], [4].