Off-target genomic DNA sites with partial homology to the Hdac1 gRNA

Off-target genomic DNA sites with partial homology to the Hdac1 gRNA refer to unintended locations within the genome that are susceptible to modification by CRISPR-Cas9 systems designed to target the Histone deacetylase 1 (HDAC1) gene. These sites share sufficient sequence similarity with the HDAC1-specific guide RNA (gRNA) to allow the Cas9 nuclease to bind and induce double-strand breaks (Fu et al., 2013, Nature Biotechnology). While HDAC1 itself is a legitimate therapeutic target for treating various cancers and inflammatory diseases, these off-target sites represent a significant safety risk rather than a therapeutic objective. Cleavage at these locations can lead to permanent mutations, chromosomal translocations, or the inadvertent activation of oncogenes (Zhang et al., 2015, Science). The identification of these sites is a critical component of the preclinical safety assessment for gene-editing therapies to prevent long-term genotoxicity. Advanced profiling methods such as GUIDE-seq and CIRCLE-seq are typically employed to map these sites across the human genome to ensure high specificity of the therapeutic intervention (Tsai et al., 2015, Nature Biotechnology). Failure to account for these sites can result in unintended phenotypic changes or cellular toxicity in patients receiving gene-editing treatments. Consequently, minimizing off-target activity is a primary challenge in the development of CRISPR-based therapeutics targeting the HDAC1 pathway.

Other names

Hdac1 CRISPR off-target sitesNon-specific Hdac1 gRNA binding sitesUnintended genomic cleavage sitesHDAC1 gRNA off-targets

Unintended double-strand DNA breaks and subsequent repair via non-homologous end joining (NHEJ) or homology-directed repair (HDR) at non-target loci due to sequence similarity with the guide RNA.