Metagenomic sequencing turns the Shroud of Turin into a biological archive
The Shroud of Turin now reads less like a single historical relic than a layered genetic record. In a new analysis published in Scientific Reports, investigators examined samples collected from the cloth in 1978 and recovered DNA from humans, bacteria, fungi, plants, animals, and Mediterranean red coral. The result is not a verdict on the Shroud’s origin. It is a molecular inventory of everything the linen has touched, absorbed, or carried across centuries of handling and exposure.
The study used PCR-free next-generation metagenomic sequencing, a method built to capture mixed DNA without narrowing the search to one species at a time. For a historical object like the Shroud, that matters. A cloth stored, displayed, transported, and handled over a long period does not preserve a clean biological signature. It accumulates one. Metagenomics is designed for exactly that kind of complexity, where human skin cells, environmental microbes, plant material, and animal traces can coexist in the same fibers.
Human lineages and a crowded microbial footprint
Among the most striking findings were multiple lineages of human mitochondrial DNA. Because mitochondrial DNA is inherited through the maternal line and exists in many copies per cell, it is often easier to recover than nuclear DNA from degraded material. Here, its presence indicates that more than one human source contributed genetic material to the cloth over time. The finding fits a simple forensic reality: a much-handled artifact becomes a biological sponge.
The microbial results were even more layered. The researchers detected bacteria associated with human skin, fungi, and microorganisms adapted to salty environments, including archaea. Archaea are single-celled organisms distinct from bacteria, and some survive in conditions that would stress or kill many other microbes. Their presence suggests the Shroud passed through environments that were not biologically simple or stable. Storage conditions, geographic movement, and repeated contact could each have left their own microbial marks.
A single cloth can therefore hold a chronicle of movement without preserving a timeline that is easy to read.
Plant, animal, and coral DNA extend the trail
The genetic traces did not stop with humans and microbes. Plant DNA included cultivated wheat, carrots, maize, bananas, and peanuts. Animal DNA included cattle, pigs, chickens, dogs, and cats. One especially unusual signal came from Mediterranean red coral.
These findings broaden the historical picture, but they do not explain it in a straightforward way. Plant and animal DNA could reflect direct handling, surrounding storage environments, contamination during transport, or later exposure in different regions. The mere presence of a species on the cloth does not reveal when that material arrived. DNA can persist, fragment, and mingle long after the original event that deposited it. In forensic terms, the sample retains evidence of contact, not a timestamp.
That limitation is built into the biology of historical specimens. Once a linen has been passed from hand to hand for generations, every transfer can add a new layer, and later layers may mask earlier ones. The resulting profile is rich, but not easily chronological.
Why the method matters more than the artifact alone
The technical advance is as important as the artifact itself. Traditional DNA approaches usually target one organism or one hypothesis at a time. Metagenomic sequencing allows investigators to interrogate all recoverable genetic material in a sample, which makes it especially useful for ancient objects, museum materials, and forensic archives. The method can reveal what standard assays miss: the coexistence of multiple species, multiple exposures, and multiple environmental histories within a single thread of linen.
This is also why the study refrains from making claims it cannot support. The DNA profile cannot establish the Shroud’s age. It cannot authenticate the cloth. It cannot distinguish original biological material from later contamination with enough certainty to answer the larger historical dispute. What it can do is document the biological complexity preserved within the official 1978 sample collection and demonstrate how modern sequencing can recover information from material gathered nearly half a century ago.
That distinction matters in historical science. Biological traces can be abundant even when the historical interpretation remains unsettled.
Forensic genomics meets contested history
The Shroud remains one of the most debated religious artifacts in the world, a linen bearing the faint image of a human figure and long associated by some believers with the burial of Jesus. Scientific interest in the cloth has never been limited to devotion or skepticism alone. It also offers a demanding test case for forensic genomics and proteomics, because the sample history is complicated, the handling history is long, and the biological signal is badly mixed.
Professor Noemi Procopio, who contributed to the collaboration at the University of Lancashire, described the samples as a rich archive of genetic information accumulated over centuries of human interaction and environmental exposure. Her comments reflect the practical value of the work: modern forensic tools can extract new data from old collections, even when those collections were gathered decades earlier for a different purpose.
In clinical terms, the closest parallel is not disease diagnosis but specimen interpretation. A degraded, mixed sample can still yield meaningful evidence if the technology is sensitive enough and the question is framed carefully. Here, the question is not whether the Shroud is authentic. It is what biological history remains embedded in the fibers.
The answer is complicated, diverse, and incomplete. The cloth carries signatures from humans, microbes, plants, animals, and coral, but the sequencing data cannot separate every layer of deposition or assign each trace a reliable age. The most consequential limitation is not the volume of DNA recovered. It is the impossibility of proving which genetic material belongs to the original fabric and which reflects centuries of later contact.