Ethics and germline gene editing.

Abstract

The current kerfuffle around the use of CRISPR/Cas9 and other gene editing technologies in human germline research is the latest in a series of related controversies at the intersection of science, medicine, and ethics [1]. Soon after a prominent ad hoc group of scientists called for a moratorium on clinical applications of germline gene editing [2], a research group from China published an article that described the genetic modification of human embryos [3]. Although these experiments were performed in nonviable, triploid embryos that were neither intended nor suitable for clinical use, the work nonetheless demonstrates how the prospect of manipulating the human germline elicits hopes and fears and triggers moral debates. Are such concerns warranted? Should research be put on hold while ethical and legal debates take place? Similar tensions arose in the past with recombinant DNA technology, assisted reproductive technologies, gene‐transfer research, human cloning, embryonic stem cell research, and mitochondrial replacement therapy. What, if anything, might be learned from these prior debates? CRISPR/Cas9 is an efficient, inexpensive, and precise method to edit genes at the level of individual nucleotides, which enables the exploration of myriad scientific questions. Moreover, it promises potential new treatments for many human diseases: HIV infection has been targeted, for example, by editing the CCR5 receptor in somatic cells using TALEN (transcription activator‐like effector nucleases) [4]. Of course, the prospect of altering the germline opens an even greater range of possibilities. For example, germline editing might be the only means of treating genetic diseases, which are otherwise fatal in utero . In addition, gene editing technologies could eventually supplant the need for assisted reproductive technologies in those who are affected by certain genetic diseases. Correcting the faulty gene in the …