MAD7 Gene Editing

MAD7 provides freedom-to-operate

While CRISPR/Cas9 revolutionized how we study biology, its intellectual property situation has always been complex. Depending on how you are using it, you might have to pay licensing fees to three different organizations.

Fortunately, in 2017, the team at Inscripta, Inc. generously gifted the scientific community with broad access to MAD7, to expand the impact of CRISPR-type technology.

MAD7 “is royalty‐free for both academic and commercial research and development use.”^1-3

MAD7 is very similar to Cas9

MAD7, or ErCas12a, is a Class 2 Type V Cas nuclease from Eubacterium rectale. Like Cas9, MAD7 is an RNA-guided nuclease. However, unlike Cas9, MAD7:

• Naturally employs a single RNA species to guide it to the target DNA sequence
• Creates double strand breaks with sticky ends rather than blunt ends
• Displays a preference for a 5′-TTTN-3′ or 5’ –CTTN-3’ PAM site rather than 5′-NGG-3′,which is preferred by Cas9.

We have years of success using MAD7 for gene editing in iPSC lines and HEK293 cells.

MAD7 applications

MAD7 can be used for many of the same applications as CRISPR/Cas9, including:

Cell line engineering

• Point mutations
• Knock-outs
• Knock-ins (less than 3 kb)

Product development

• Cell therapy
• Gene therapy (producer lines)
• Antibody or protein expression

^References

1. ^{Rojek, J. , Basavaraju, Y. , Nallapareddy, S. , Baumgartner, R. , Schoffelen, S. & Pedersen, L. Mad7: an IP friendly CRISPR enzyme. Authorea. 2022. Available from: 10.22541/au.162863226.68733765/v1}
2. ^{Price MA, Cruz R, Bryson J, Escalettes F, Rosser SJ. Expanding and understanding the CRISPR toolbox for Bacillus subtilis with MAD7 and dMAD7. Biotechnology and Bioengineering. 2020;117(6):1805-1816. doi:10.1002/bit.27312}
3. ^{Mund M, Weber W, Degreif D, Schiklenk C. A MAD7‐based genome editing system for Escherichia coli. Microbial Biotechnology. 2023;16(5):1000-1010. doi:10.1111/1751-7915.14234}