Why Ancient DNA? Building a Public Demonstration of The BioChain

Building a public demonstration of The BioChain

The BioChain was built around a simple problem: scientific evidence rarely lives in one place. A biological sample may begin in the physical world, acquire an identifier in one system, be processed in another, generate data stored somewhere else, contribute to an analysis performed through a different computational environment, and eventually support a conclusion published in yet another system. Every individual system may work perfectly — the difficulty lies between them.

Can we reconstruct the complete journey from the original biological material to the eventual scientific claim? Can we establish which records are related, what happened between them, who or what performed each transformation, and whether anything changed along the way? That is the problem The BioChain is designed to address.

But demonstrating infrastructure of this kind presents its own challenge. A private pharmaceutical, diagnostic or genomic workflow could demonstrate the technology, but much of the underlying evidence could not be made public. A simplified synthetic demonstration could be completely open, but would conveniently remove precisely the messiness that makes real scientific provenance difficult. We wanted something different: a real scientific domain, real samples, real sequencing data, real publications, real repositories, real inconsistencies — and evidence that anyone could independently inspect. We found it in the past.

Ancient BioChain

Ancient BioChain is a public demonstration environment for The BioChain. It uses publicly available ancient DNA and archaeogenomic information to demonstrate how The BioChain can connect evidence distributed across multiple sources without attempting to replace those sources. That distinction matters: Ancient BioChain is not intended to become another ancient DNA repository. The repositories already exist, the publications already exist, the datasets already exist — The BioChain provides the layer between them, and its job is to record and expose relationships.

Specimen → Sample → Laboratory → Sequencing → Repository → Processing → Dataset → Analysis → Publication

The result is an evidence graph through which a user can move backwards and forwards — starting with an ancient individual and following its data into subsequent research, or starting with a published result and tracing the evidence backwards towards its biological origin. That is the demonstration.

Why ancient DNA?

Ancient DNA is almost perversely well suited to testing provenance infrastructure. The evidence is fragmented in more ways than one: physical specimens may have archaeological identifiers, samples may receive laboratory identifiers, sequencing data acquire repository accessions, publications introduce their own naming conventions, and aggregated datasets may subsequently assign further identifiers. One biological individual can consequently acquire multiple digital identities.

The information surrounding that individual can also change. Dating may be refined, archaeological interpretation may be revised, sequence processing methods may improve, contamination estimates may change, and samples can be included in successive versions of datasets. Meanwhile, the original biological material is finite and often irreplaceable. It creates exactly the kind of environment in which provenance should matter.

A deliberately difficult demonstration

We could have constructed an elegant demonstration dataset specifically for The BioChain, where everything matched, every identifier resolved, and every relationship was known — and it would have proved very little. Real scientific data are not like that. Ancient BioChain therefore begins with existing public resources and asks The BioChain to deal with reality: records will be incomplete, identifiers will disagree, relationships will sometimes be implicit rather than explicit, metadata will vary between sources, the same individual may be represented differently in different datasets, and some provenance chains will terminate unexpectedly.

This is not noise that we intend to hide from the demonstration — it is part of what we are demonstrating. A provenance system should not create certainty where the underlying evidence does not provide it. If a relationship is established, the system should be able to show why. If a relationship is inferred, that distinction should remain visible. And if the chain is broken, the break should be visible too.

Connecting rather than replacing

This illustrates an important principle behind The BioChain. Scientific organisations already operate complex ecosystems of specialist systems — laboratory information management systems, sequencing platforms, repositories, analysis pipelines, databases, electronic records and research platforms all perform valuable functions. Replacing all of them with a single enormous system is neither realistic nor desirable.

The BioChain takes a different approach: leave the evidence where it belongs, and connect its history. A repository accession can continue pointing to the repository, a DOI can continue identifying a publication, an archaeological record can remain in its specialist system, and a computational output can remain within the infrastructure that generated it. The BioChain records the relationships necessary to understand how those objects form part of the same evidence chain. Ancient BioChain makes that architecture visible using information that can be inspected publicly.

From a tooth to a scientific claim

Imagine beginning with a tooth excavated from a burial several thousand years ago. The physical object is sampled, DNA is extracted, a sequencing library is prepared, and sequence data are generated. Raw reads are deposited in a public repository, processed, and the resulting genome is incorporated into a population dataset. Researchers analyse that dataset, and a paper subsequently makes a claim about population movement — a claim that may be expressed in a few sentences, behind which sits an extensive chain of evidence.

The BioChain asks whether that chain can be traversed. Where did this result originate? Which specimen contributed to it? Which data were generated from that specimen, and where are those data stored? Which processes transformed them, and which version of the dataset contained them? Which publications used them, and what other findings subsequently depended upon them? Those questions are relevant to ancient genomics — and they are also relevant far beyond it.

The same architecture, different evidence

Replace the ancient tooth with a modern diagnostic specimen and the conceptual problem remains:

Patient sample → Laboratory → Sequencing → Analysis → Interpretation → Clinical or public-health decision

Replace it with an animal-health investigation:

Animal → Sample → Laboratory → Pathogen sequence → Epidemiological analysis → Outbreak decision

Or food provenance:

Farm → Animal → Processing → Batch → Testing → Distribution → Investigation

Or collaborative research:

Specimen → Experiment → Instrument → Dataset → Analysis → Publication

The objects change; the principle does not. Evidence moves, evidence changes, and evidence crosses systems and organisational boundaries — and decisions increasingly depend on being able to establish where that evidence came from. That is why we chose ancient DNA.

Ancient pathogens: where the demonstration becomes particularly interesting

Ancient pathogen genomics provides an especially powerful extension of the demonstration. A sample originally collected to investigate an ancient human population can contain something else entirely: evidence of infection. Pathogen DNA identified within ancient human remains can subsequently contribute to reconstructed pathogen genomes, phylogenetic analyses and our understanding of historical epidemics — so the evidence chain can cross disciplines:

Archaeology → Human genomics → Pathogen genomics → Evolutionary biology → Epidemiology

This is exactly the kind of boundary The BioChain is intended to cross. The system does not need the evidence to remain within one discipline, because provenance is concerned with relationships between evidence, not departmental ownership of it. An ancient plague genome and a contemporary pathogen sequence are separated by centuries; as digital evidence, however, both present remarkably similar questions — where did this sequence originate, how was it produced and transformed, what analysis used it, and what conclusion depends upon it?

An open test

There is another reason for building Ancient BioChain: you do not have to take our word for it. The demonstration is based on public scientific information. Where licensing and access permit, users can follow identifiers back to their sources, inspect publications, examine repository records and compare what The BioChain represents against the underlying evidence. That makes Ancient BioChain more than a showcase — it makes it a test. If we claim that The BioChain can reconstruct distributed evidence chains, a public demonstration allows researchers, developers and potential users to examine that claim for themselves. We think infrastructure concerned with trust should be demonstrated in a way that permits scrutiny.

Why Origins?

This journal exists alongside that demonstration. We called it Origins because provenance is ultimately concerned with origins — not merely the biological origins studied through ancient DNA, but the origins of evidence itself. Where did this record come from? What preceded it? What transformed it? What depends upon it? How confidently can we reconstruct that history?

Origins will follow those questions through archaeogenomics, ancient pathogens, computational biology, scientific data infrastructure and provenance. Some articles will explore the science behind datasets entering Ancient BioChain; others will examine individual evidence chains, investigate places where those chains break, and document what we learn from trying to connect scientific evidence that was never originally designed to form a single connected record.

Ancient DNA gives us an extraordinary window into biological history. For The BioChain, it provides something else as well: a difficult, public and independently inspectable test of whether we can preserve the history of evidence itself.