# Enzymatic long-DNA synthesis by Ansa Biotechnologies

Canonical page: https://technooptimist.io/biotech/enzymatic-dna-synthesis
Frontier: [Biotech](https://technooptimist.io/biotech.md) · Field: Synthetic biology · Company: [Ansa Biotechnologies](https://technooptimist.io/companies/ansa-biotechnologies.md)
Stage: Scaling (5 of 5: Research → Proto → Pilot → Deploy → Scaling)
Updated: last update 2025-10-22, facts checked 2026-10-11
Goal: Let biologists order any DNA they can design, including long, repetitive or GC-rich sequences that chemical synthesis can't make, in weeks rather than months, so designing biology is no longer bottlenecked by writing DNA.
Status: Selling 50 kb sequence-perfect clonal DNA since Oct 2025, delivered in under 25 business days.
Next milestone: Scaling capacity and product range (vectors, larger scale), target 2026

## Milestones

| Status | Milestone | Date | Slip |
| --- | --- | --- | --- |
| Done | Founders publish practical enzymatic DNA synthesis (Nature Biotech) | 2018 |   |
| Done | $68M Series A to launch a synthesis service | Apr 2022 |   |
| Done | 50 kb clonal DNA launched after early access at 20+ institutions | Oct 2025 |   |
| Done | $54.4M Series B to expand US manufacturing | Oct 2025 |   |
| Current | Scaling capacity and product range (vectors, larger scale) | 2026 |   |

## Upcoming events

- **2026**: Scaling capacity and product range (vectors, larger scale)

## Most important updates

- **22 Oct 2025**: Ansa launches 50 kb sequence-perfect clonal DNA, the longest synthetic DNA sold commercially. After an early-access programme with more than 20 institutions, Ansa launched clonal DNA constructs up to 50,000 bases, verified by long-read sequencing and delivered in under 25 business days. ([our story](https://technooptimist.io/stories/ansa-launches-50-kb-sequence-perfect-clonal-dna-the-longest-synthetic-7b6568a2.md) · [original source](https://www.drugdiscoverynews.com/ansa-biotechnologies-redefines-what-s-possible-in-dna-synthesis-with-50-kb-sequence-perfect-clonal-product-16751))
- **1 Oct 2025**: Ansa raises $54.4M Series B led by Cerberus Ventures to expand US DNA manufacturing. Ansa closed $45.2M with $9.2M more committed, a $54.4M Series B led by Cerberus Ventures, to expand US manufacturing capacity. ([our story](https://technooptimist.io/stories/ansa-raises-54-4m-series-b-led-by-cerberus-ventures-to-expand-us-dna-96cfd72f.md) · [original source](https://www.biospace.com/press-releases/ansa-biotechnologies-secures-54-4-million-in-series-b-financing-to-redefine-how-scientists-access-synthetic-dna-with-industrys-first-guaranteed-on-time-service))
- **11 Apr 2022**: Ansa Biotechnologies closes $68M Series A to commercialise enzymatic DNA synthesis. Ansa raised a $68M Series A led by Northpond Ventures to build high-throughput synthesizers and launch a DNA synthesis service. ([our story](https://technooptimist.io/stories/ansa-biotechnologies-closes-68m-series-a-to-commercialise-enzymatic-dna-93d12f67.md) · [original source](https://www.biospace.com/article/releases/ansa-biotechnologies-closes-oversubscribed-68-million-series-a-financing-to-power-the-next-era-of-dna-enabled-industries))

## Current obstacles

- **Cost per base**: From $0.28 per base, a 50 kb construct still costs on the order of $14,000; large libraries need cheaper writing.
- **Biosecurity screening**: Longer, easier DNA raises the stakes of screening orders for dangerous sequences, which the industry still standardises.

## Physics limits

- **Errors compound with length**: Each added base succeeds slightly less than 100% of the time, so the share of perfect molecules falls exponentially with length; very long DNA must be assembled and checked.
- **Writing is slower than reading**: Synthesis adds one base per cycle, whereas sequencing reads billions of bases in parallel, so writing remains far costlier per base than reading.

## How it works

### Tethered enzyme: One letter per enzyme

Each polymerase carries a single nucleotide on a linker; it adds that one letter, then is cut away, so the strand grows base by base.

### Gentle chemistry: Water, not harsh solvents

Chemical synthesis uses acids that damage long strands; the enzymatic route keeps DNA intact, so fragments run far longer.

### Assembly: Fragments to 50 kb plasmids

Long fragments are joined into full constructs and grown as clones in cells.

### Verification: Long-read checked

Every construct is sequenced end to end with long reads so customers get sequence-perfect DNA.

## Spec sheet

| Spec | Enzymatic long-DNA synthesis | Provenance |
| --- | --- | --- |
| Longest clonal construct | 50 kb | reported |
| Direct synthesis fragment | Up to 900 bases | reported |
| 50 kb delivery | Under 25 business days, guaranteed | reported |
| Price | From $0.28 per base pair | reported |
| Chemical synthesis constructs | Rarely above 10 kb | reported |

Provenance: reported = stated by the company; estimated = our estimate; sample = a sample figure.

## About Ansa Biotechnologies

Emeryville, California company that writes DNA with an enzyme instead of harsh chemistry, selling sequence-perfect DNA up to 50,000 bases long for gene therapy, antibody and synthetic-biology work.

- Sells clonal DNA up to 50 kb, which it calls the longest sequence-perfect synthetic DNA on the market (Oct 2025).
- Direct enzymatic synthesis of fragments up to 900 bases; chemically made constructs rarely exceed 10 kb.
- Raised $68M Series A (2022) and $54.4M Series B (2025); manufactures only in the US.

- Headquarters: US
- Status: private
- Raised: $122M
- Last round: Series B $54M, 1 Oct 2025, led by Cerberus Ventures
- Website: https://www.ansabio.com
- People: Jason T. Gammack (Chief Executive Officer); Daniel Lin-Arlow (Co-founder); Sebastian Palluk (Co-founder)
- Partners, customers, investors: Microsoft (partner)

Company page: https://technooptimist.io/companies/ansa-biotechnologies.md

## Related programs

Everything in Biotech: https://technooptimist.io/biotech.md

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