AAVS1 Safe Harbor
Targeting with Cas9
Targeted integration at a
safe genomic locus
AAVS1 targeting kits
- Easy, precise knock-in of any gene
- Consistent, robust transgene expression
- Simplified construction of isogenic cell lines
- Minimal off-target integration
- Streamlined CRISPR/Cas9 library screening
AAVS1 Safe Harbor Site Targeting System
Delivering consistent, robust transgene expression, the AAVS1 safe harbor site is a preferred target for gene knock-ins. Insertion at the site has been shown to be safe with no phenotypic effects reported, and the surrounding DNA appears to be kept in an open confirmation, enabling stable expression of a variety of transgenes.
System Biosciences (SBI) now offers a wide range of tools to help researchers take advantage of the power of the AAVS1 safe harbor site, from elegantly designed vectors and kits that simplify knock-in of any gene while minimizing off-target effects, to a cell line that stably expresses Cas9 for streamlined genome-wide screening efforts. SBI's line of AAVS1 safe harbor site tools is just another way SBI transforms the latest technological advances into robust tools that accelerate your research.
AAVS1 Safe Harbor Site Targeting
A crucial application of CRISPR-Cas9 technology has been targeted genome engineering of human pluripotent cells such as hESCs and iPSCs, as these cells have the capacity for many broad-based applications in studying human disease. Traditional viral-mediated gene transfer into these cells has often led to variable and sometimes unpredictable results, namely transgene silencing and/or acquisition of tumorigenic phenotypes through insertional mutagenesis. To address these shortcomings, guide RNAs have been designed and validated to target the human AAVS1 (also known as PPP1R12C) locus, a well-validated "safe harbor" in the human genome (Sadelain et al. 2011). A safe harbor is defined as a region of the genome that is considered to be both transcriptionally active and its disruption does not lead to discernable phenotypic effects. The targeting of the AAVS1 locus by site-specific nucleases and homologous recombination of donor plasmids bearing GFP or antibiotic selection markers have been previously demonstrated in human ESC and iPS cells. The targeting efficiencies within these two cell types has been reported as ranging between 40-80% (Hockemeyer et al. 2011). Notably, all successfully targeted cells showed expression of GFP as well as several pluripotency markers (e.g. Oct4, Sox2, TRA-1-60). These cells retained the ability to differentiate into tissue representing all three germ layers, suggesting that targeting and modification of the AAVS1 locus results in stable transgene expression and no discernible "off-target" phenotypes.