Are you looking for a simple means to boost the efficiency of gene editing and also to reduce the off-target? Yes, it does exist – in one word: 4-hydroxy Tamoxifen. That’s the HIT-CAS9.

Hybrid drug inducible CRISPR/Cas9 technology, HIT-Cas9

Zhao et al. revealed tight and effective drug control of the CRISPR Cas9 based on 4-Hydroxytamoxifen.

They built a fusion between a mutated human estrogen receptor (ERT2) and the Cas9 endonuclease, which makes the CRISPR Cas9 dependent on 4-hydroxytamoxifen.

Drug control of gene editing
4-OHT inducible Cas9 activity

That control of the CAS9 activity reduces the off-target and boosts the on-target activity. This HIT-Cas9 activity is 25-fold higher than wild-type Cas9.

Vector-free CRISPR Cas9 delivery

Why not go further to the therapeutics prospectives?

We can provide all-in-one plasmids expressing the Cas9 and the sgRNA or even lentiviral particles to deliver Cas9 and sgRNA.

However, a vector free approach ensures not random integration in the genome and so it is the guarantee of genome integrity and gene editing specificity. Unfortunately, delivery of the Cas9 protein can be challenging due to its size.

The solution is to use Cas9 mRNA with CleanCap Capping so that the efficient product in the vial is close to 100%.

For the HIT-Cas9, customization of the Cas9 is required. You may prefer do it yourself and produce your mRNA with the CleanCap technology.

Or, we can produce the custom mRNA for you and you would benefit by the way to the Mammalian optimized UTRs of the Trilink in vitro transcription vector.

Any questions about CRISPR Cas9 gene editing? Get in touch with me through the comments field below, I’ll be pleased to advise!

Written by Dimitri Szymczak, PhD
Dimitri Szymczak is a Technical Support Specialist and Product Manager at tebu-bio, and a fan of capoeira in his spare time.