Writing DNA to create synthetic life

This article is part of the Emerging biotech atlas series. Read the introductory article here. We will update this section whenerver new pieces are published. Subscribe to receive pieces these via email (select “Biotech”).

An introduction to DNA Synthesis

What is it?

In synthetic biology, DNA synthesis refers to the act of using chemicals or enzymes to build DNA sequences from scratch. What makes this synthetic? Well, unlike DNA replication, the process of copying DNA molecules which is happening all the time inside living organisms – DNA synthesis allows scientists to write genetic sequences instead of merely reading them. This design work happens in silico (on computers) and is built into DNA molecules in vitro (in the lab). This isn’t about tweaking existing DNA; it’s about composing entirely new biological scripts from scratch. Think of it as building with LEGO bricks, except each piece is a nucleotide (A, T, C, G), and the final  construction might be a synthetic gene, or an organism designed to fight climate change.

Why should this grab your attention?

This biotechnology technique is helping to craft vaccines in weeks instead of years, encoding entire troves of data into strands of DNA, and designing organisms that eat pollution. The technology is becoming widespread and accessible to the public through different services and business models. What was once a niche lab tool is now reshaping industries, from medicine to materials, with all the signs of a quiet revolution.

How might it reshape our world?

Picture a world where we could grow our buildings instead of constructing them, where medicines are brewed by engineered microorganisms in tiny pharmaceutical factories, and where we could shift some food production towards methods that nurture rather than harm our planet. DNA synthesis is the key to this bio-based future, particularly in Europe where it’s driving a shift toward a sustainable bioeconomy. By harnessing the power of engineered biological systems, we’re potentially opening doors to everything from climate-friendly foods to renewable materials, life-saving medicines, and clean energy.

What are the risks and how can Europe safeguard the future?

But every revolution has its shadows. Rolling out these tech capabilities unlocks brilliant biosolutions, but also introduces new vulnerabilities in biosecurity, ethics, governance, and global equity.  In practical terms, wider access to DNA synthesis and AI-driven design raises biosecurity risks, including the potential for using this technology for illegal or dangerous purposes such as weaponisation of pathogens. While industry groups like the International Gene Synthesis Consortium act as “genetic spell-checkers” of sorts, screening orders for dangerous sequences, their voluntary system has gaps big enough to drive a virus through. Europe now has the challenge of playing a leading role in building guardrails that protect without stifling the very innovation that could stimulate EU growth and bioeconomy.

From reading to writing DNA: engineering biology’s future

Let’s first start with the basics of DNA. It is useful to think of DNA as a molecule that encodes the information necessary for life. It is usually represented as a long string of characters composed of four distinct letters called nucleotides: A, T, C, G. At the molecular level, the way in which nucleotides choose to pair allows a double helix to form, as two complementary strands intertwine to form the DNA helix. The way the letters are ordered and organized defines how the biological instructions are encoded in DNA. A human genome is composed of around 3.2 billion nucleotides, arranged across 23 pairs of chromosomes. And within these chromosomes are around 20,000 genes that carry the instructions for building all the proteins in the human body.

The mastery of reading DNA through next-generation sequencing (NGS) technologies since the mid-2000s marks one of science’s most remarkable accelerations – progress on sequencing has  outpaced even Moore’s Law^[1],^[2]. This big leap in sequencing speed and accuracy has transformed our understanding of biological systems, enabling ambitious initiatives like the European ‘1+ Million Genomes’ project^[3] that analyses genetic information at unprecedented scale in the search of cures and treatments.

But reading DNA was just the first chapter. The emergence of sophisticated DNA writing and synthesis technologies^[4] has fundamentally altered our relationship with biology, moving us from observers to architects of living systems. This shift has already yielded remarkable achievements: engineering microorganisms that serve as microscopic factories for sustainable materials^[5], developing new therapeutic and novel drug delivery systems^[6], and even storing digital data in DNA’s compact architecture^[7].

The convergence of these reading and writing capabilities is catalysing a new bioeconomy that extends far beyond traditional biotechnology. Just as the digital revolution transformed information processing, DNA synthesis is turning biological code into a foundational manufacturing platform. Companies are engineering microorganisms to produce everything from spider silk^[8],^[9] to artificial meat^[10] without agricultural inputs, while others are developing programmable cells that can sense and respond to disease^[11]. This industrial-scale biological engineering represents more than just technological progress. It’s enabling a fundamental reimagining of how we produce materials, medicines, and food.

The resulting surge in demand for synthetic DNA is driving rapid technological advancement in synthesis methods, working to optimise on three critical dimensions: scale, purity, and cost.

Each improvement makes new applications feasible, creating a virtuous cycle of innovation. Advanced synthesis techniques are also enabling more complex biological designs, from engineered protein therapeutics to synthetic chromosomes^[12]. These developments are particularly crucial for emerging fields like cell therapy, synthetic biology, and biomaterial production, where precise control over genetic sequences enables entirely new classes of products.

Within this evolving landscape, DNA synthesis is emerging as more than a scientific tool – it’s becoming the key enabler of a bioeconomy that could help address some of humanity’s most pressing challenges. 

The ability to write and edit DNA with precision opens possibilities that were unimaginable just decades ago. As synthesis technology becomes more accessible and automated^[14], we’re entering an era where engineered biology could transform everything from medicine to manufacturing, promising solutions that are not just innovative, but inherently sustainable and circular. For example, the European Commission highlights that “industrial biotechnology that uses microorganisms or their biological components will enable new processes that use less resources and energy and produce less waste and polluting emissions. ^[15].

Most importantly these solutions have the potential to massively contribute to our economy. The EU market for industrial biotechnology-derived products is expected to grow from €28 billion in 2013 to €50 billion in 2030, representing a 7% annual growth rate^[16].

The European Commission is well aware of the potential of these sectors and is developing a new Bioeconomy Strategy, expected by the end of 2025, to guide the sustainable and circular bio-based economy while promoting bio-based innovation and responsible use of biotechnology15.

DNA synthesis: when biology meets engineering

Several factors have advanced the technology to its current state4. To recap,  the first leap began with reading DNA, culminating in the Human Genome Project’s completion which marked the milestone that showed us the sheet music of life, so to speak. The second phase is where we currently find ourselves, focusing on writing and editing this code. This capability lies largely in research labs, but it is driving a third phase of practical applications that touch everything from medicine to agriculture. As we have covered, it is important to keep in mind that our capacity to write has lagged behind, creating what industry experts call the “DNA writing gap”. This gap currently limits our ability to rapidly explore and develop applications; it’s a crucial bottleneck in advancing synthetic biology and its uses in daily life.

From chemical to enzymatic manufacturing

Traditional DNA synthesis is based on phosphoramidite chemistry^[17]. This method, which has served as the industry’s backbone since the 1980s, builds DNA sequences nucleotide by nucleotide on solid supports, a bit like stringing pearls on a necklace. While this approach revolutionized our ability to create DNA, it comes with significant limitations. The process requires toxic organic solvents, demands specialised expertise, and perhaps most crucially, hits a wall at above 300 nucleotides 4  – as beyond this, the accumulation of errors is too high. This limitation is particularly frustrating given that most interesting biological applications require much longer sequences16.

Enter enzymatic DNA synthesis (EDS), nature’s own answer to the DNA writing challenge. At its heart lies terminal deoxynucleotidyl transferase (TdT), an enzyme that acts like nature’s own DNA printer ^[18]. This shift from pure chemistry to biology-inspired approaches marks one of the most significant transitions in the field’s history.

The beauty of enzymatic synthesis lies in its elegance and environmental friendliness. Instead of harsh chemicals, it operates under conditions similar to those in living cells. However, what makes TdT fascinating is also what makes it challenging to control – its ability to add nucleotides without needing a template^[19]. Indeed, TdT shows natural preferences for certain nucleotides, affecting how quickly each is added –  leading to inefficient nucleotide addition as sequences grow longer.

These limitations are being tackled by the research and development departments of several companies specialised in the field of molecular biology and DNA manufacturing ^[20].

Industry offers diverse solutions to common challenges

The DNA synthesis landscape has spawned remarkably different technical approaches, each addressing specific aspects of the synthesis challenge. These innovations are more than incremental improvements, they actually demonstrate fundamentally new ways of thinking about DNA manufacturing.

Consider Molecular Assemblies’ collaboration with Codexis. Their engineered TdT variant, capable of operating at temperatures up to 70°C, solves one of the field’s most persistent challenges: preventing DNA from folding into problematic structures during synthesis. This is like preventing a ribbon from tangling while trying to measure it – heating it makes it easier to keep it straight and as such efficiently add the next nucleotides. Other innovations came from Ansa Biotechnologies who engineered TdT variants to provide precise control over nucleotide addition^[19]. This system works like a molecular assembly line where each worker (the enzyme) is responsible for adding exactly one building block before passing the baton. With this approach they manage to synthesize 1,005-nucleotides-long DNA fragments.

Twist Bioscience’s approach to the synthesis challenge is different but exemplifies how silicon technology can revolutionise biological processes ^[4],^[19]. By miniaturising synthesis onto semiconductor chips, they’ve achieved what seemed impossible a decade ago: parallel synthesis of thousands of DNA sequences simultaneously ^[14],^[19]. This innovation has driven costs down dramatically, approaching €0.1–0.3 per nucleotide  for gene fragments – a stark improvement from historical costs, though still not quite at the cost level reached for DNA sequencing ^[8]. The impact of this cost reduction extends beyond mere economics. As synthesis becomes more affordable, entirely new applications become feasible. Consider data storage – a field where DNA’s incredible density (about 215,000 hard drives   per gram, assuming one hard drive has 1 terabyte storage capacity) makes it an attractive alternative to traditional electronic storage ^[7]. The DNA Data Storage Alliance’s efforts to create standardised approaches for this technology demonstrate how synthesis capabilities are pushing the boundaries of what’s possible ^[21].

As we look toward the future, the most promising developments appear to lie in hybrid approaches that combine multiple technologies for achieving longer sequences while maintaining high accuracy. Some approaches rely on the integration of enzymatic synthesis on semiconductor chips^[19]. It enables both precise control and parallel synthesis capabilities, suggesting a future where the best aspects of different technologies work in concert with the claimed capabilities of manufacturing gene sized fragments. The Austrian company Ribbon Biolabs is tackling this challenge differently through convergent assembly methods ^[22], enabling the synthesis of DNA fragments exceeding 10 kilobases, a remarkable achievement that points toward even greater possibilities ^[23].

Benchtop DNA printers: lab-scale factories for genetic code

The DNA synthesis revolution has traded industrial warehouses for lab benchtops. Today’s DNA synthesisers are compact, user-friendly, and powerful enough to fit next to labs’ microscopes. Modern platforms merge synthesis, assembly, and quality control into a single box ^[19]. It’s the biotech equivalent of a 3D printer that designs, prints, and inspects its own creations.

The $200,000 price tag for something like DNA Script’s Syntax4 might raise eyebrows, but it is important to consider the entire value cycle. Traditional DNA synthesis often involves outsourcing to centralised facilities, adding weeks of delays and per-base fees ^[19]. Most importantly, three main manufacturers are driving virtually the entire market’s growth in this space^[24]. Benchtop printers flip this business model: researchers can draft a genetic sequence at noon, synthesise it by lunch, and test it in cells the following day. In therapeutic development, where a single protein tweak can mean the difference between a failed trial and a blockbuster drug, this is transformative. Startups like Ansa Biotechnologies have slashed antibody design cycles from months to weeks using in-house synthesis ^[19].

An important aspect of this future trend is democratisation. Much like how desktop publishing puts graphic design in everyone’s hands, these devices let labs bypass the “genetic middlemen.” Need a custom plasmid to test a CRISPR edit? Print it. Want to engineer a microbe that glows when it detects pollution? No outsourcing required. The ripple effects are profound: scientists in labs will be able to tackle projects once reserved for Pharma R&D departments, and startups can iterate without burning venture capital on sequencing invoices.

Yet challenges linger. While synthesis costs have dropped to €0.1–0.3 per base (compared to €10 in the 1990s), the “DNA writing gap” persists. Editing genomes remains far cheaper than building them from scratch. Nevertheless the trajectory is clear: we’re transitioning from an era of biological observation to one of creation. Benchtop DNA printers are turning labs into ateliers of living code—where the line between design and discovery blurs, and innovation cycles spin faster than a centrifuge. But as these printers proliferate, so do questions around biosecurity, ethics, governance, and global equity ^[25].

Democratising DNA: how biotech will redefine global risk

Policymakers in this field now have the challenge of thinking about both current biotechnology capabilities and their exponential evolution. Rolling out of DNA synthesis technologies raises considerations that touch on the ethics of synthetic life, the design of research and innovation policies, the dynamics of societal understanding and trust, as well as the shifting terrain of geopolitical competition and global governance.  While these broader issues deserve dedicated exploration, the next section focuses on the biosecurity implications of this technology – and why this potential governance challenge  is immediate and consequential for European policymakers.

The DNA synthesis field is shifting from centralised, resource-intensive labs to streamlined manufacturing—think of it as moving from a factory assembly line to a desktop printer, but for genetic material. Today, companies can synthesise DNA strands up to 20,000 nucleotides long ^[19], a capability which allows the production of genetic material sufficient for viruses like polio, HIV or ebola (Figure X). Progress in synthesising entire genomes (bacterial, yeast, or even synthetic chromosomes) remains experimental, but the direction of travel is clear. Each breakthrough—whether in DNA assembly speed, cost, or accuracy—pushes what’s feasible further into territory once deemed speculative.

A 2023 study found that advanced biotechnologies now transition from expert labs to skilled non-specialists in under five years—a timeline projected to shrink to 3.5 years by 2030 ^[26]. What begins as a tool for PhDs in well-funded labs soon becomes accessible to startups, hobbyists, and classrooms ^[27]. This diffusion isn’t inherently negative, but it demands safeguards that evolve as quickly as the technologies themselves – a real challenge for conventional policymaking processes.

While companies which are members of the International Gene Synthesis Consortium (IGSC) screen DNA orders against databases of known pathogens—a process akin to checking luggage for prohibited items—these practices are neither universal nor bulletproof. One study revealed that even within the IGSC, member companies use differing pathogen databases and screening thresholds, with a low rate of stress-testing for vulnerabilities like false negatives ^[25].Critically, outside the consortium, risks escalate: smaller and local providers may skip a thorough customer identity verification, and in certain cases lack formal procedures to report suspicious orders to law enforcement—a gap called “the most pressing vulnerability” ^[25].

In 2023, MIT researchers tested the DNA screening system by requesting DNA fragments of the 1918 influenza virus from 38 providers ^[28]. Only one flagged the order. The remaining 37 fulfilled it without scrutiny. As is so often the case, voluntary measures alone cannot ensure universal compliance. Compounding the issue, the cost of DNA synthesis continues to decline rapidly, but the fixed expenses of robust screening do not. For smaller providers, this creates a financial asymmetry—like selling affordable products while bearing high security costs. Without binding standards, economic pressures may incentivise skipping screenings, however unintentionally.

Just this year, a team led by Microsoft, working with international biosecurity organisations, conducted an “AI red-teaming” exercise to test DNA screening. Using freely available AI design tools, they produced over 76,000 computer-generated variants of 72 hazardous proteins and submitted them to four biosecurity screening software (BSS) providers—systems used by DNA synthesis companies to check customer orders for dangerous sequences. Many variants went undetected at first, as most safeguards only flag sequences that closely match those already on a watchlist. When the red-teaming group applied DNA obfuscation—breaking and shuffling gene fragments—detection became even harder. After several BSS providers refined their tools, detection was improved to about 97% of variants. The missed variants resemble low-risk sequences, and the researchers highlighted the need to agree on what counts as “potentially hazardous,” since AI-assisted protein design can now create variants that blur the line between safe and  unsafe.^[29]

Internationally, consensus is building around DNA synthesis screening as a linchpin of modern biosecurity. Recent publications from the World Health Organization ^[30] and the Convention on Biological Diversity (CBD) ^[31]  have outlined the potential utility of screening of orders for DNA materials as part of a range of actions which actors involved in biosecurity governance can take to safeguard these technologies. Scientific bodies are aligning with these approaches ^[32], with major journals and research consortia now treating DNA screening as non-negotiable due diligence. Finally some nation states are taking the lead in implementing screening measures domestically. For example the U.S. advanced toward mandatory DNA screening with its Securing Gene Synthesis Act (2023) ^[33], since then, the 2024 OSTP Framework set screening expectations for federally funded DNA synthesis, but Executive Order 14292 (May 2025) has directed agencies to revise it, leaving the final rules still to be defined.  Over in the UK, in October 2024, the government released  voluntary guidance for users and providers of synthetic nucleic acids — setting out baseline expectations for customer and sequence screening, whilst leaving the door open to legislate in this area.

How is this technology governed at the EU-level?

Commercial DNA synthesis in the EU currently sits outside a clearly defined regulatory framework. At the level of individuals wanting to order pieces of DNA, there’s no binding requirement for companies to screen customers or DNA sequences for dangerous constructions. While some providers have taken on voluntary commitments, there’s nothing in EU law that explicitly mandates them to do so. This has practical implications. Without clear, enforceable obligations, the risk of misuse lingers in the background. Whether accidental or deliberate, the creation of harmful biological agents using synthetic DNA remains within the realm of the possible.

None of the current EU frameworks for biosafety, genetic modification, and export control were designed specifically with modern DNA synthesis technologies in mind. As a result, the governance approach is patchy — anchored in principles that predate the speed and scale of current innovation. In practice, the industry self-regulates. Some companies in the EU follow voluntary screening protocols, including through leading initiatives such as the industry-led IGSC, whose members screen the complete DNA and translated amino acid sequences of every gene order against its Regulated Pathogen Database. That’s a worthwhile interim measure. But it’s not enough for a future in which synthesising a virus could become increasingly feasible .

The primary legal lever governing DNA synthesis is EU dual-use export controls. Technology like DNA printers fall into the category of “dual-use”, items and technologies that can be used for both civil or military uses. Regulation (EU) 2021/821 ^[34] is the EU’s main instrument here. It sets out which items require export authorisation and takes its cue on which items and technologies to control from international coordination efforts like the Wassenaar Arrangement and the Australia Group. The latter, notably, includes nucleic acid synthesisers and related software on its control list. So far, this is where most of the EU’s formal governance sits: not in how these technologies are developed or used domestically, but in how they move across borders. We also shouldn’t forget that it’s Member States that ultimately enforce this regulation, using their own governance systems and capabilities to manage movements of such technologies. Beyond screening, it’s unclear how easy and consistent reporting and response processes are for suspicious orders across Member States.

The EU’s ambition to position biotechnology as a strategic economic pillar makes securing these technologies, and embedding the kind of regulatory clarity that sparks innovation, a priority. To maintain public trust and global competitiveness, the EU will need to integrate biosecurity into its innovation agenda. The forthcoming EU Biotech Act and related biotech initiatives could bridge this divide by turning biosecurity from a bottleneck into a catalyst for competitive and safe innovation. ​The EU has an opportunity to lead in strengthening global biosecurity standards and turn it into a competitive advantage. Having said that,  science is a global effort, with ideas and innovations flowing across borders, and so the EU must engage in and shape international coordination to make a meaningful impact.

Where we could go next

What’s missing is a fit-for-purpose, forward-looking governance framework for technologies designed for “writing” DNA. One that acknowledges both the promise of synthetic biology capabilities and the potential for harm. This thinking is already happening at the national and international level, trying to piece together initiatives like screening of risky customers and sequences with wider considerations of how to mitigate the risks from other scientific discovery and manufacturing processes. Looking into the near future, the OECD’s 2025 ‘Synthetic biology in focus: Policy issues and opportunities in engineering life ^[35]’ signalled future work to develop a recommendation for the responsible development of synthetic biology – a step that could help build international consensus on governing the convergence of engineering biology with AI and automation.

For the EU, the challenge and opportunity go further. The forthcoming Biotech Act is an opening to tackle governance gaps as well as positioning biotechnology as a true strategic pillar — economically, industrially, and in terms of security. That means coupling stronger safeguards with active investment in DNA synthesis capabilities as an enabling infrastructure. This could take the  form of shared-use facilities (think national or regional biofoundries) as well as  enhanced capabilities through connecting them to secure, cloud-enabled systems that can standardise screening, protect sensitive data, and make capabilities widely available for research and innovation.

DNA synthesis is a foundational technology for many applications across biotech, and while most enforcement sits with Member States, there’s room (and opportunity) for EU-level action to help align approaches, identify opportunities for joint action, and close the gaps. This is a strategic tech which, if nurtured, could help bring Europe closer to unlocking growth across the entire biotech value chain: strengthening capabilities from early-stage research to commercial-scale manufacturing.

We’ll close this chapter with a thought that is already embedded in many industries: what if safety-by-design approaches were treated as catalysts for economic growth? Embedding safety principles into EU research funding and infrastructure — for example, ensuring projects rely on synthesis providers with audited practices — could help seed a competitive, innovation-driven synthesis ecosystem across Europe.

Endnotes