knock-in Article 1 CRISPR 1 CRISPR Cas system 1 CRISPR-Cas Systems 1 CRISPRi/a 1 Cas9 1 Clustered Regularly Interspaced Short Palindromic Repeats 1 Gene Editing 1 Genome 1 RNA sequence 1 RNA targeting 1 RNA, Guide 1 clinical protocol 1 clustered regularly interspaced short palindromic repeat 1 criteria 1 durability 1 expression 1 gene editing 1 gene interaction 1 gene knock-in 1 gene knock-out 1 gene knockout 1 genetics 1 genome 1 genome editing 1 genomic safe harbor 1 guide RNA 1 guide design 1 human 1