Scientists unlock DNA from ancient parchments without damage, revealing hidden histories

For centuries, the parchments locked away in libraries and museum vaults have held secrets that no one could safely extract. These documents—legal records, maps, religious texts—were written on animal skin, which means they carry within their fibers the genetic material of the creatures they came from. But accessing that DNA meant risking damage to irreplaceable artifacts, so the secrets stayed buried. Now researchers have found a way to unlock them.

The breakthrough is almost mundane in its simplicity. A team led by Tim Stinson at North Carolina State University discovered that a dry cytology brush—the same tool used in routine medical screenings—can gently lift cellular material from parchment without leaving a mark. The brush collects enough genetic information to sequence and analyze, yet the manuscript remains untouched, its surface unmarred. It sounds like a small thing, but for institutions responsible for preserving cultural heritage, it changes everything.

To prove the method works, the researchers tested it on 91 manuscripts housed in Duke University's Rubenstein Library. The documents ranged across geography and time: some came from England, others from Ethiopia, and they spanned from the late eighth century to the early twentieth. For each one, they brushed the parchment, extracted the cells, and used forensic-grade sequencing technology to read the genetic code embedded in the material. What emerged was a new kind of historical evidence, one that sits at the intersection of biology and scholarship.

The implications ripple outward in unexpected directions. Matthew Breen, a geneticist at NC State's College of Veterinary Medicine, points out that parchment DNA can reveal how domesticated animals evolved over centuries—how breeds developed, how diseases moved through livestock populations, when and where certain animals were raised. Because parchment was in use for so long and often recorded detailed information about daily life, the genetic material it contains becomes a window into agricultural history that written records alone cannot provide. A medieval document about a monastery's sheep might now tell us not just what the monks wrote, but the actual genetic makeup of the animals they tended.

The same approach works for understanding trade routes and the movement of goods and animals across continents. It works for determining where a manuscript was made, by identifying the species and origin of the animal whose skin became the page. It works for uncovering details of everyday life that scribes never thought to record—the presence of certain animals, the prevalence of particular diseases, the patterns of human and animal movement that shaped medieval Europe and beyond.

But the real barrier to this research was never technical. It was institutional. Libraries and museums have legitimate reasons to be protective of their collections. These are irreplaceable objects, often centuries old, sometimes unique. The idea of researchers taking samples—even small ones—raised understandable concerns about damage and loss. That hesitation is what made this work so important. By demonstrating that samples could be collected without harm, Stinson and his colleagues opened a door that institutions had kept carefully closed.

The researchers acknowledge they are essentially pioneers in a new field, one that brings together geneticists, historians, archaeologists, and conservators in ways that rarely happened before. They are seeking funding to continue the work, to expand beyond the initial 91 manuscripts and explore what other parchments might reveal. The potential is vast. Thousands of historic documents sit in archives around the world, each one a genetic time capsule waiting to be read. The technology exists. The method is proven. What remains is the work of actually doing it—of systematically unlocking the biological stories that centuries of parchment have been holding all along.