Specific synthetic chimeric xenonucleic acid guide RNA; s(XNA-gRNA) for enhancing CRISPR mediated genome editing efficiency

The invention provides xenonucleic acids and synthetic chimeric xenonucleic acid guide RNA; s(XNA-gRNA) for enhancing crispr mediated genome editing efficiency. The invention also provides methods and compositions for inducing CRISPR/Cas-based gene editing/regulation (e.g., genome editing or gene expression) of a target nucleic acid (e.g., target DNA or target RNA) in a cell. The methods include using single guide RNAs (sgRNAs) that have been chemically modified with xeno nucleic acids which enhance gene regulation of the target nucleic acid in a primary cell for use in ex vivo therapy or in a cell in a subject for use in in vivo therapy. Additionally, provided herein are methods for preventing or treating a genetic disease in a subject by administering a sufficient amount of a sgRNA that has been chemically modified with xeno nucleic acids to correct a mutation in a target gene associated with the genetic disease.