Ancient Blood Cells Discovered in 5,300-Year-Old Mummy
In a breakthrough for both archaeology and forensic science, researchers announced the discovery of intact red blood cells in Oetzi, the remarkably preserved body of a man who died approximately 5,300 years ago in the Italian Alps. Found frozen by hikers in 1991 with an arrow embedded in his back, Oetzi has been the subject of ongoing scientific investigation for decades. The blood cell discovery, published in the Journal of the Royal Society Interface, represents the oldest red blood cells ever identified.
Previous attempts to locate blood within the mummy had failed, as red blood cells are fragile structures that typically degrade rapidly after death. An earlier study published in the Lancet had detected hemoglobin, a blood protein, in a wound on Oetzi’s hand, but researchers had assumed that intact cells could not have survived the millennia.
Advanced Microscopy Reveals Preserved Cells
The research team, led by Albert Zink at the Eurac Institute for Mummies and the Iceman in Bolzano, Italy, partnered with scientists at the Center for Smart Interfaces at the University of Darmstadt in Germany. They applied a technique called atomic force microscopy to thin tissue slices taken from the area surrounding the fatal arrow wound.
Atomic force microscopy works by dragging a metal tip just a few atoms wide across a sample surface, tracking its movement to generate a three-dimensional map at extraordinary resolution. The scans revealed structures displaying the characteristic doughnut shape of red blood cells.
To rule out contamination, the team verified their findings using Raman spectroscopy, a laser-based analytical method. The results confirmed the presence of both hemoglobin and fibrin, a protein associated with blood clotting.
New Evidence on the Iceman’s Final Hours
The detection of fibrin proved particularly significant for reconstructing the circumstances of Oetzi’s death. Because fibrin appears in fresh wounds and breaks down relatively quickly, its presence directly contradicted an earlier theory suggesting that Oetzi survived for several days after being struck by the arrow.
According to Zink, the fibrin evidence indicated that the arrow wound was inflicted shortly before death, narrowing the timeline of what has been called the world’s oldest murder case. Oetzi’s full genome had been published earlier the same year, revealing details such as his probable eye color and blood type, adding another layer to one of archaeology’s most studied individuals.
The researchers also noted that their analytical methods could have practical applications in modern forensic science, where accurately determining the age of blood samples remains a persistent challenge.
