US Patent 9234213 Compositions and methods directed to CRISPR/Cas genomic engineering systems

The invention relates to engineered CRISPR/Cas9 systems for genomic modification in mammalian cells. The present specification describes the design and testing of a polynucleotide encoding the Streptococcus pyogenes (S. pyogenes) Cas9 protein, where the nucleotide sequence has been optimized for expression in mammalian cells. The specification also describes all-in-one systems for RNA-guided genome engineering in mammalian cells, including human cells.