How Old Is That Book? DNA May Hold the Answer

Hide and Seek: genetic material from animal-skin pages may trace medieval manuscript origins

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Long before musty old paper volumes and Google Book Search, most tomes in medieval Europe were written on animal skins—a practice which might now hold the key to tracing their origins.

Timothy Stinson, an associate English professor at North Carolina State University in Raleigh, has started using DNA testing to track the history and age of medieval manuscripts. His goal: to create a DNA database from the books with known publication dates and places (such as calendars and histories) in an effort to use the genetic information gleaned from them as a baseline to date those manuscripts whose backgrounds are unknown.

"There are these tantalizing hints that this would work for parchment," he says of the DNA testing, "but no one was really using it." He says that in addition to tracing the roots of written documents, genetic clues may help piece together manuscripts that were separated over time.

Thousands of fragile manuscripts still survive from the Middle Ages (roughly 400 to 1500 CE), a time when most of Europe's population was illiterate, and monks transcribed nearly all of the books that circulated around the continent. Until recently, scholars relied on visual analysis (such as handwriting samples) to trace the origin of most ancient texts. But Stinson says that more precise genetic analyses are possible because the preferred "paper" of the day was thin parchment made from the skin of local cattle, sheep or goats. "DNA offers much more specific information, but no one's mapped it yet," he says.

Stinson and his team tested five pages from a 15th-century French manuscript and found genetic material from at least two different cows. "If you can do this to a 2,000-year-old mummy," Stinson says, "you can do this to a book from the 15th century."

DNA testing has previously been used to study Greek manuscripts as well as the Dead Sea Scrolls. Nikos Poulakakis, an assistant professor of biology at the University of Crete in Greece who conducted some of that research, says he's eagerly awaiting the results of the U.S. study. He notes that in addition to revealing important information about old manuscripts and library collections, the genetic material may also shed light on ancient trade routes and even domestic animal herds of the time.

Medieval manuscripts often were written on pages made from the skins of as many as 100 different animals, according to Stinson. But scholars speculate that, at least until the mid-15th century, most books were made from local herd animals, which could make tracing their point of origin fairly reliable.

Tom Gilbert, a geneticist at the University of York in England, points out, however, that, "working with material from domestic animals is tricky." Many animals within a herd may be closely related—or even identical twins—and parchments may have been treated with other animal products, either during creation or previous conservation, which could confuse results. Stinson will present his findings later this month at the Bibliographical Society of America in New York City.

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe