The recently developed RNA-guided clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated 9 (Cas9) nuclease system has progressed to be an invaluable technology for genome manipulation in somatic cell types and germline model organisms.While the unprecedented advance in human embryo gene editing research has great potential in next-generation therapeutics,it raises various ethical conces that need to be addressed before being translated for clinical use.Here,we discuss the current and potential applications of CRISPR/Cas9 technology and its limitations in clinical applications,as well as ethical and legal considerations in the treatment,disease prevention or disability in somatic cells or human embryo via gene editing.