Jean K. CarrMaría Mercedes ÁvilaManuel Gómez CarrilloHoracio SalomónJesse HierholzerVeerachai WatanaveeradejMaría A. PandoMónica NegreteKevin L. RussellJosé L. Sánchez2026-03-222026-03-22200110.1097/00002030-200110190-00002https://doi.org/10.1097/00002030-200110190-00002https://andeanlibrary.org/handle/123456789/44070Citaciones: 161Twenty-one HIV-1 strains from three South American countries, 17 of which were pre-screened by envelope heteroduplex mobility assay (HMA), were studied. Ten out of 10 HMA subtype F and four out of seven HMA subtype B strains were actually BF recombinants upon full genome analysis. Two BF recombinants from Argentina and two from Uruguay had the same structure, representing a new circulating recombinant form termed CRF12_BF(ARMA159). Twelve other BF recombinants had structures related to CRF12 but with additional segments of subtype B; each was unique. BF recombinants were temporally and geographically widespread, found as early as 1986-1987 in vertically infected Argentinian children and in Argentina, Uruguay, and Bolivia.enHeteroduplexGenomeVirologyBiologyLentivirusGenetic diversityHuman immunodeficiency virus (HIV)Recombinant DNAPeripheral blood mononuclear cellGeneticsarticle