With the advent of efficient, easy-to-use genome editing by CRISPR–Cas9, editing human embryos is now possible, providing tremendous opportunities to study gene function and cell fate in early human development. The technique can also be used to modify the human germline. Unresolved questions about pre-implantation human development could be addressed by basic research using CRISPR–Cas9. In this Perspective, we discuss advances in human genome editing and consider ethical questions and potential clinical implications of this technology.
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We thank members of the Niakan, J. Turner and R. Lovell-Badge laboratories for helpful discussions and comments on the Perspective. We are grateful to J. Brock in the Scientific Illustrations team for generating figures. Work in the Niakan laboratory is supported by the Francis Crick Institute, which receives its core funding from Cancer Research UK (FC001120), the UK Medical Research Council (FC001120), and the Wellcome Trust (FC001120).
The authors declare no competing interests.
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A correction to this article is available online at https://doi.org/10.1038/s41556-019-0451-x.
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A. Lea, R., K. Niakan, K. Human germline genome editing. Nat Cell Biol 21, 1479–1489 (2019) doi:10.1038/s41556-019-0424-0