Multiple V1/V2 env variants are frequently present during primary infection with human immunodeficiency virus type 1.

Journal of virology
2004
https://researcherprofiles.org/profile/1439501
15452240
Ritola K, Pilcher CD, Fiscus SA, Hoffman NG, Nelson JA, Kitrinos KM, Hicks CB, Eron JJ, Swanstrom R