CRISPR/Cas Proteins

Custom Cas Protein Service

With our custom Cas protein production, we deliver tailored enzymes across RUO to cGMP—built to meet your exact editing goals. Backed by proprietary engineering platforms and rapid gene synthesis, we offer defined yield, purity, and activity—with guaranteed packages available. Projects can be completed in as little as 2 weeks, with regulatory support for IND submissions. From early discovery to therapeutic development, our custom solutions accelerate your CRISPR pipeline.

Guaranteed delivery

Yield and purity guaranteed

Industrial-leading Speed

Production in as little as 2 weeks

Activity Assay Development

Established protocol developed in-house

Scale-up Capacity

From µg to grams

Service Details

Interested in cGMP Cas proteins?

We offer cGMP Cas9 proteins off-the-shelf, as well as custom cGMP bacterial expression for a variety of CRISPR proteins.

Case Studies

• GenCRISPR SpCas9 - high editing efficiency

  GenCRISPR SpCas9 demonstrated high gene editing efficiency in both in vitro cleavage tests and HEK293T cells.

  In vitro cleavage test

  

  Gene knockout efficiency_HEK293 T cell

  
• GenCRISPR SpCas9 - batch-to-batch consistency

  Gene knockout efficiency_293 T cells & Jurkat cells

  

  GenCRISPR SpCas9 is used for gene knockout in 293T cells and Jurkat cells. As shown in the figure, the gene knockout efficiency of three batches shows no significant difference.

• GenCRISPR SpCas9 - batch-to-batch consistency

  GenCRISPR SpCas9 is used for gene knockout in 293T cells and Jurkat cells. As shown in the figure, the gene knockout efficiency is equivalent to that of the leading supplier I.

  
• GenCRISPR eSpCas9 minimum off target effect

  The fidelity and editing efficiency of GenCRISPR eSpCas9 Protein were evaluated against wildtype Cas9 on Jurkat cells and primary T cells. GenCRISPR eSpCas9 exhibited a superior ability to reduce off-target edits.

  Low off-target effects_Jurkat cells

  

  Low off-target effects_ Primary T cells

  
• GenCRISPR eSpCas9 Shows high editing efficiency comparable to wild-type SpCas9

  GenCRISPR eSpCas9 exhibits comparable knockout and knock-in efficiency to the wildtype SpCas9 in both Jurkat cells and primary T cells.

  High Knockout_ Jurkat cells and Primary T cell

  

  High Knock-in_ Primary T cell

  
• GenCRIPSR™ Ultra eSpCas9 (mt) batch-to-batch consistency

  The GenCRIPSR™ Ultra eSpCas9 (mt) shows high batch-to-batch consistency, with no significant differences in cell viability and consistent knockout/knock-in efficiency across the three batches at any concentration.

  KO at TRAC sites in HEK293T cells

  

  GFP KI at RAB11A in Jurkat cells

  
• GenCRISPR eSpCas9 shows lower off-target effects compared to HiFi Cas9

  GenCRISPR eSpCas9 exhibits lower off-target effects compared to HiFi Cas9 products from leading suppliers, while its knockout and knock-in efficiencies are equivalent to or exceed those of the leading suppliers.

  Low off-target effects_HEK293 T cell

  

  High Knockout efficiency_HEK293 T cell

  

  High Knock-in efficiency_Primary T cell

  
• Base editor (ABE8e)

  Gene editing efficiency in Jurkat cells using ABE8e RNP

  

  High A to G conversion across different doses

  

  ABE8e protein effectively knocks out B2M protein

• Prime editor

  Gene editing efficiency in HEK293T cells using PE7 RNP at 50 pmol

  

  PE7 mediated targeted 5 bp deletions at the HEK3 locus in HEK293 cells

  

  No significant impact on cell viability

• GenCRISPR™ Ultra ErCas12a shows enhanced knockout efficiency

  Higher editing efficiency was observed for β2M knockout in Jurkat cells using GenCRISPR™ Ultra ErCas12a-3NLS, His-tag (Cat. No. RC00012) compared to Supplier A, as assessed by NGS and flow cytometry for gene and protein knockout.

  

  
• GenCRISPR™ Ultra ErCas12a shows enhanced knock-in and multi-gene editing efficiency

  Higher knock-in efficiency with triple knockout was observed in primary human T cells using GenCRISPR™ Ultra ErCas12a-3NLS, His-tag (Cat. No. RC00012) compared to all other suppliers’ products tested.

  

See what researchers worldwide have achieved with our Cas proteins:

Resources

CRISPR/Cas Nuclease Solutions

From Discovery to GMP – The Complete Toolkit for Next-Generation Gene Editing

Free Download

Catalog mRNA, saRNA, ciriRNA, LNPs and ladders

Ready To Use RNA and LNPs– Empowering Discovery and Innovation

Free Download

CRISPR RNP Handbook

Enabling RNP-mediated CRISPR gene editing and transforming life science research

Free Download

GenCRISPR™ Gene Editing Solutions

All solutions you need for a successful CRISPR gene editing project

Free Download

FAQs

• 1. What types of off-the-shelf Cas proteins does GenScript offer?

  GenScript offers a broad catalog of ready-to-use Cas nucleases in protein format, including Cas9, Cas12a, Cas13a, MAD7, Base Editors, and Prime Editors. These are available in both RUO (Research Use Only) and GMP-grade formats to support applications from early discovery to clinical manufacturing.

• 2. Can GenScript create custom Cas proteins for my specific project?

  Yes. Our custom Cas protein service can engineer and produce nucleases precisely to your specifications—covering RUO through cGMP production. We deliver defined yield, purity, and activity, with guaranteed performance packages and production timelines as short as two weeks.

• 3. How do I choose between catalog and custom Cas proteins?

  Our catalog products are ideal for widely used gene editing applications where validated, off-the-shelf options meet your needs.

  Custom Cas proteins are recommended if you require unique formats, novel nucleases, enhanced fidelity, altered PAM specificities, or other custom specifications.

• 4. What quality control standards do GenScript’s Cas proteins meet?

  All Cas proteins undergo rigorous QC testing for purity, activity, and minimal off-target effects. GMP-grade nucleases are manufactured following current Good Manufacturing Practice (cGMP) guidelines and are compliant with FDA/EMA/PMDA/NMPA regulations.

• 5. How quickly can GenScript deliver Cas proteins?

  Catalog products are available with rapid turnaround and global shipping. Custom Cas protein projects can be completed in as little as two weeks after sequence confirmation, depending on complexity and production scale.

• 6. Are GenScript’s Cas proteins suitable for therapeutic applications?

  Yes. We offer GMP-grade enzymes specifically designed to meet the high performance, traceability, and compliance requirements of therapeutic development—from preclinical through commercial production.

• 7. What licensing or IP considerations should I be aware of?

  The catalog nucleases in our portfolio are licensed from the Broad Institute, providing access to validated products with streamlined IP pathways. For custom projects, our team can work with you to address licensing and regulatory considerations to minimize delays in your program.

• 8. What support does GenScript provide during development?

  Our scientists provide technical support, troubleshooting, and regulatory guidance, including data packages to support IND filing. We work as an extension of your team from concept to scale-up.

• 9. What applications do GenScript’s Cas proteins support?

  Our Cas nucleases are validated for a range of applications, including:

  • Targeted genome knockout and knock-in (e.g., via Cas9, Cas12a, MAD7)
  • Precision single base editing (ABE, CBE)
  • Prime editing for seamless corrections without the need for a DNA donor template
  • RNA editing (Cas13a)
  • Cell line engineering and therapeutic development
• 10. How do I start a Cas protein project with GenScript?

  You can browse our catalog Cas proteins online for immediate online ordering, or contact our custom services team to discuss your specifications, timelines, and regulatory requirements.