The controversial gene-editing breakthrough claimed by Dr He Jiankui may be a pivotal moment in human development, says Doug Clark

There have been many 2001: A Space Odyssey Monoliths in mankind’s history: the wheel, the development of agriculture, the internal combustion engine. Not all of these, however, have been physical. There have been several such step-changes in our thinking, our ethics and morals. The Christian church has fought against many of these. Galileo was only one of the most famous victims of such.

I suspect that Dr He Jiankui’s work on gene editing in the Southern University of Science and Technology in Shenzhen will turn out to be one of these Monolith moments (Scientist broke law creating gene-edited girls, China says, 30 November). Pioneers, particularly in the life sciences, will always run the risk of surpassing man’s moral and ethical evolution.

Doug Clark

Currie, Midlothian

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