A near full-length HIV-1 genome from 1966 recovered from formalin-fixed paraffin-embedded tissue

Significance Inferring the precise timing of the origin of the HIV/AIDS pandemic is of great importance because it offers insights into which factors did—or did not—facilitate the emergence of the causal virus. Previous estimates have implicated rapid development during the early 20th century in Central Africa, which wove once-isolated populations into a more continuous fabric. We recovered the first HIV-1 genome from the 1960s, and it provides direct evidence that HIV-1 molecular clock estimates spanning the last half-century are remarkably reliable. And, because this genome itself was sampled only about a half century after the estimated origin of the pandemic, it empirically anchors this crucial inference with high confidence.