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What happened in China in 2018 involving gene-edited human babies?

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CRISPR-Cas9; gene editing — gene editing The CRISPR-Cas9 gene-editing complex from the bacterium *Streptococcus pyogenes*.

In late 2018, a Chinese scientist announced the birth of the world’s first gene-edited human babies, a pair of twin girls. The infants were reported to have been modified using CRISPR-Cas9 technology to carry an edited gene intended to reduce their risk of HIV infection.12

This event sparked significant global controversy and ethical debate regarding the genetic engineering of humans. The ability to perform germ-line modifications—changes that are heritable—raised profound moral concerns about the potential for creating "designer babies" and the risks of introducing unintended genetic errors. In response, many researchers and bioethicists, including pioneers in the field, called for a moratorium on editing human eggs, sperm, or embryos, emphasizing that the technology’s long-term safety and ethical implications remain inadequately understood.12