Scientists have made new progress with gene-editing tools, especially CRISPR-Cas9, which can now change genes more accurately. These tools were first used to treat patients, but now researchers can also change genes in embryos or reproductive cells. This means any changes could be passed down to future generations, and the discussion about this technology is now moving from the lab to possible real use in clinics.

This is important because editing genes in embryos, called germline editing, changes human DNA forever. Many experts worry because these genetic changes could cause problems for future generations if mistakes are made.

Now, international health organisations are under pressure to create clear, global rules for using gene-editing technology. Different countries have different laws, and some people are concerned that without global agreement, researchers could travel to countries with weaker laws to do risky experiments.