Researchers at North Carolina State University and Duke University have cracked a problem that has haunted historians and geneticists alike: how to peer into the genetic secrets of centuries-old parchments without destroying them. Using nothing more invasive than a cytology brush—the same tool used for medical Pap smears—they've unlocked 1,300 years of hidden information locked within animal skin manuscripts, from trade routes to the evolution of livestock breeds.
The breakthrough matters because parchment, made from animal hides, has been the document of choice across Europe, the Middle East, and parts of Africa for millennia. Legal deeds, maps, religious texts, and historical records were all inscribed on skin that still carries the genetic signature of the animals it came from. For centuries, that genetic information has been inaccessible to researchers—accessing it meant risking damage to irreplaceable cultural artifacts. Now it doesn't have to.
For their study, Tim Stinson, an associate professor of English at NC State, and Matthew Breen, the Oscar J. Fletcher Distinguished Professor of Comparative Oncology Genetics in NC State's College of Veterinary Medicine, led a team that collected cellular samples from 91 manuscripts housed in Duke University's Rubenstein Library. These parchments spanned geographies as vast as their time periods: documents originated from England to Ethiopia and were written between the late eighth and early 20th centuries. The researchers simply rubbed each parchment with a cytology brush and extracted the cellular material left behind, then applied forensic-level, next-generation sequencing technologies to amplify and analyze the genetic sequences.
"Because parchments have been in use for so long, and often record detailed historical information, the genetic information they contain can also shed light on the evolution of domesticated farm species, how breeds developed over time, livestock diseases and so on," Breen explained in the paper, published in the journal Manuscript Studies. The genetic data can reveal when and where a manuscript was actually made—information that written records alone might obscure or leave ambiguous.
What makes this work particularly significant is that it solves a critical access problem. For years, institutions responsible for preserving these documents have been understandably protective, wary that any sampling would compromise their integrity. The cytology brush method changes that calculation entirely. "We're able to extract a tremendous amount of new information from these parchments without harming them," Breen says. "This will hopefully engender trust with those organizations that are responsible for preserving these historic documents."
Stinson and Breen frame this as an emerging field with vast untapped potential. They're seeking funding to expand their work, exploring how state-of-the-art genetic analysis can answer empirical questions about historical cultural and agricultural practices that have long remained opaque. "We have a remarkable opportunity here," Breen notes. "It is essentially a whole new field, bringing together a truly interdisciplinary range of expertise spanning fields from genetics to medieval history."
The implications ripple outward. Ancient manuscripts could now help us understand how diseases moved through livestock populations, how agricultural systems evolved, and how global trade networks functioned centuries ago—all without ever turning a page the wrong way.