Forty years later, the families of those lost during the Cold War combat in Vietnam may finally get their wish: a definitive account of what happened to their loved ones and, at this point, their ancestors. The march of progress in genetic analysis could give them this chance, as the country prepares to host the largest mass identification effort in history, potentially involving hundreds of thousands of bodies in the end.

Genomics pioneer Craig Venter told Nature that when he was a 21-year-old serving in the medical corps at the time, he “never imagined that such a project could ever become possible… We thought of body counts as statistics — now, decades later, it may be possible to put names to them.”

The difficulty in identifying the bodies comes down to several unique aspects of Vietnam and the conflict there, not all of which have been solved just yet. The first is the condition of each individual body — a lot of time has passed, and these skeletons have been sitting in a very biologically active part of the world. Natural decay happens very quickly in Vietnam, and any DNA trapped in the bones will be in a much weaker state than DNA trapped for an equivalent amount time in, say, the northern Balkans. It’s only with cutting-edge techniques in DNA “amplification” (repeated duplication to create testable amounts of DNA from a tiny sample) and analysis that scientists can offer a way forward.