--- title: LockSeq Service | Off-Target Confirmation, DNA-In to Report-Out | Countagen description: Send us your DNA and off-target coordinates. We return a UMI-corrected variant allele frequency report in 15 business days. No capital expenditure. No infrastructure. End-to-end service. --- [![Logo\_horizontal\_colored logo with black text](https://www.countagen.com/hubfs/Logo_horizontal_colored%20logo%20with%20black%20text.png)](https://www.countagen.com/?hsLang=en) - [Home](https://www.countagen.com) - [Technology](https://www.countagen.com/technology?hsLang=en) - [Resources](https://www.countagen.com/resources?hsLang=en) - [FAQ](https://www.countagen.com/faq?hsLang=en) - [About Us](https://www.countagen.com/about-us?hsLang=en) [REQUEST A QUOTE](https://www.countagen.com/about-us?hsLang=en#get-in-touch-form) Off-target confirmation service # Confirm every on- and off-target edit, from coordinates to report. You define the targets. We design the panel, run LockSeq in our Stockholm lab and deliver an analysed report in 15 business days. No instrument investment, no bioinformatics overhead. [Request a quote](https://www.countagen.com/contact?hsLang=en)[See a sample report](https://www.countagen.com/lockseq-sample-report?hsLang=en) Panels designed for 1,000+ sites  ·  0.1% VAF detection limit  ·  Illumina, MGI & ONT LockSeq report · results Illustrative data 290 / 300 sites reportable 3 on-target sites edited | Site | Edited | Control | Call | | --- | --- | --- | --- | | **DP-001** on-target | 71.1% | 0.0% | Edited | | **DP-002** on-target | 77.1% | 0.0% | Edited | | **DP-187** exon | 0.42% | 0.29% | Background | | **DP-004** intron | 0.0% | 0.0% | No variant | Mean variant frequency, 3 replicates[View full sample report →](https://www.countagen.com/lockseq-sample-report?hsLang=en) Used by gene-editing teams at ![Danish Cancer Institute](https://www.countagen.com/hs-fs/hubfs/Danish%20Cancer%20Institute.png?width=634&height=346&name=Danish%20Cancer%20Institute.png) ![Karolinska CRISPR Functional Genomics Unit](https://www.countagen.com/hs-fs/hubfs/Karolinska%20CRISPR%20Functional%20Genomics%20Unit.png?width=944&height=472&name=Karolinska%20CRISPR%20Functional%20Genomics%20Unit.png) ![University Freiburg](https://www.countagen.com/hs-fs/hubfs/University%20Freiburg.png?width=766&height=102&name=University%20Freiburg.png) ![NIST Gene Editing Consortium](https://www.countagen.com/hs-fs/hubfs/NIST%20Gene%20Editing%20Consortium.png?width=950&height=226&name=NIST%20Gene%20Editing%20Consortium.png) > LockSeq has been instrumental in scaling our validation panels for off‑target candidates, a key process in the safety assessment of our gene writing platform. Countagen's team approachable expertise and dedicated support with data interpretation have added value to our research. > > **Marta Sanvicente García, PhD** > Bioinformatics Scientist, Integra Therapeutics The regulatory context ## FDA draft guidance calls for orthogonal off‑target confirmation The FDA's April 2026 draft guidance on genome editing safety calls for confirmation methods independent of the nomination assay for IND‑enabling submissions. As panels grow, keeping sensitivity and complete target coverage gets harder. Missing sites are data blind spots that can turn into delays and regulatory risk. LockSeq is built for exactly this step. 1 Nominate Candidate sites from your nomination assay or in silico prediction. 2 Confirm with LockSeq An orthogonal, targeted readout of every nominated site in your edited samples. 3 Report Edit frequencies per site, ready for your safety package. How it works ## What's included in every LockSeq study An end-to-end service: you focus on your therapy, we deliver high-confidence edit detection. 01 · Scoping ### Project scoping We review your edit design, gRNAs and nominated off‑target coordinates, and add in silico nomination where needed. Usually within 24 hours. 02 · Panel ### Panel design Padlock probes for all your on‑ and off‑target loci, designed for 1,000+ sites per reaction. Add new targets later without redesigning the panel. 03 · Lab ### Sequencing Library prep and sequencing in our Stockholm laboratory, on Illumina, MGI or Oxford Nanopore. 04 · Report ### Consensus report UMI-corrected VAF per site with indel profiling, coverage charts and raw data (FASTQ + BAM). 15 business days from DNA receipt. ![High-Level Workflow](https://www.countagen.com/hs-fs/hubfs/High-Level%20Workflow%20(3).png?width=2000&height=448&name=High-Level%20Workflow%20(3).png "High-Level Workflow") #1 — PROJECT SCOPING #### We review your edit design, gRNA sequences, and nominated off-target coordinates. Where needed, we can supplement with in silico nomination. Turnaround: Usually within 24 hours from first contact to project specification. #2 — PANEL CUSTOMIZATION #### We design padlock probes for all your on- and off-target loci — up to 1,000+ sites per reaction. Probes are validated *in silico* before synthesis. #### Mix-and-match of new targets across development stages without panel redesign. #3 — TECHNICAL EXECUTION #### LockSeq library preparation and sequencing are performed in our Stockholm laboratory. Illumina and Oxford Nanopore platforms confirmed. #4 — CONSENSUS REPORTING #### You receive a UMI-corrected variant allele frequency report with indel profiling, coverage uniformity charts, and raw data (FASTQ + BAM). Standard turnaround: 15 business days from DNA receipt. 0.1% VAF detection limit 1,000+ sites per reaction, by design 15 days DNA to report, business days 3 platforms: Illumina, MGI & ONT Why LockSeq ## Built for large panels without the usual blind spots ### High-confidence edit detection Gap-fill ligation captures targets before amplification, and UMI consensus sequencing suppresses technical errors, for confident calls down to 0.1% VAF. ### Fewer dropouts, better coverage Designed to minimise target dropout in highly multiplexed workflows, so large panels stay complete. ### One workflow, any scale From single-site confirmation to large off‑target panels in the same workflow. Reconfigure targets without assay redesign. #### High-Confidence Edit Detection LockSeq uses gap-fill ligation to capture target molecules prior to amplification. UMI-based consensus sequencing suppresses technical errors, enabling confident detection of edits down to 0.1% VAF across panels exceeding 1,000 targets. #### Fewer Dropouts. Better Coverage. LockSeq is designed to minimize target dropout in highly multiplexed workflows. By reducing assay complexity and potential molecular interactions, the platform improves target representation and supports more complete genomic characterization across large panels. #### One Workflow. Any Scale. Reconfigure targets without assay redesign. LockSeq supports everything from single-site confirmation to \>1,000-plex off-target characterization in a single workflow, with demonstrated compatibility across Illumina and ONT. Pricing ## Projects start from €1,000 For example, a panel of up to 25 sites with 2 samples. Price scales with sites and samples. Most projects are scoped within 24 hours. **Every quote includes:** panel design · library prep & sequencing · UMI-corrected VAF per site · indel profiling · coverage charts · raw data (FASTQ + BAM) [Request a quote](https://www.countagen.com/contact?hsLang=en)[See a sample report](https://www.countagen.com/lockseq-sample-report?hsLang=en) [Request a quote](https://www.countagen.com/contact?hsLang=en) Proudly partnering with [![ClearCut Biolabs](https://www.countagen.com/hubfs/ClearCut_logo_provided.png)](https://clearcutbiolabs.com) [![Countagen\_Logo\_White](https://www.countagen.com/hubfs/Logo_horizontal_colored%20logo%20with%20white%20text.png)](https://www.countagen.com) | Countagen AB Nobels väg 16 171 65 Solna Sweden | Registered supplier on [Scientist.com](https://app.scientist.com/providers/countagen-ab) [![Scientist.com](https://www.countagen.com/hs-fs/hubfs/Scientist-com.png?width=1244&height=259&name=Scientist-com.png)](https://app.scientist.com/providers/countagen-ab) | | --- | --- | ### Product - [LockSeq Service](https://www.countagen.com) - [FAQ](https://www.countagen.com/faq?hsLang=en) ### Technology - [Technology](https://www.countagen.com/technology?hsLang=en) - [Resources](https://www.countagen.com/resources?hsLang=en) ### Company - [About Us](https://www.countagen.com/about-us?hsLang=en) © 2026 Countagen AB All rights reserved [Terms of Use](https://www.countagen.com/terms-of-use?hsLang=en) [Privacy Policy](https://www.countagen.com/privacy-policy?hsLang=en) [Cookie Policy](https://www.countagen.com/cookie-policy?hsLang=en) [Powered by Atlas - a B2B SaaS HubSpot theme](https://www.kalungi.com/atlas-hubspot-theme-for-b2b-saas-software)