It is applied to the fertilized ovum or early stage embryos I think. At least that seems to be what He Jiankui did: https://www.npr.org/2023/06/08/1178695152/c

It is applied to the fertilized ovum or early stage embryos I think. At least that seems to be what He Jiankui did: https://www.npr.org/2023/06/08/1178695152/china-scientist-he-jiankui-crispr-baby-gene-editing https://www.npr.org/2023/06/08/1178695152/china-scientist-he...