The shifting ethics of gene editing
TAMPER WITH THE DNA of future generations? I had always thought this was a moral line in the sand that would never be crossed — that it had been inscribed with weighty moral force by the pioneers of genetic engineering in the 1970s. I was mistaken. The era of genetic engineering began in 1972, when Paul Berg at Stanford University learnt to cut and paste DNA from one virus to another. Dubbed the father of genetic engineering, he realised he’d opened Pandora’s box. People were worried: would scientists create monsters?
Berg called for a moratorium and organised the 1975 Asilomar Conference on Recombinant DNA. Amidst the windswept Monterey pines and crashing waves of California’s coast, 140 scientists, lawyers, journalists and ethicists discussed the potential dangers of GM microbes and came up with guidelines to safely contain them.
I had thought that was the moment when the line in the sand was drawn: thou shalt not tamper with the DNA of a human sperm, egg or a newly formed embryo. But on probing, I find no evidence. “There wasn’t a moral line in the sand,” Asilomar co-organiser David Baltimore, now an emeritus professor at California Institute of Technology, told me. “There was the simple recognition we were not techically in a position to consider such a thing”.
Nevertheless, since then many countries have considered germ-line gene modification beyond the pale, and enshrined this belief in legislation.
For decades, the regulatory harness held firm. We’ve had genetically-modified bacteria that produce our drugs, pest-resistant cotton, goats producing spider silk in their milk, gene therapy trials for sick people. But no tampering with the human gene pool.
Until April of last year. Making use of the new CRISPR technique – so accurate it has been named genetic editing rather than engineering – Chinese researchers “edited” the DNA of unviable human embryos to correct a gene that causes severe anaemia.
Sure enough, it sounded the alarm bells. Jennifer Doudna, the Berkeley scientist who developed CRISPR in 2013, said she’d stopped sleeping at night. NIH head Francis Collins condemned the trespass saying it was “viewed almost universally as a line that should not be crossed”. But it’s certainly not a universal reaction. Like Oxford ethicist Julian Savulescu, author of our cover story, Baltimore agrees there is a strong moral case for editing the human germ line. In a bookend to Asilomar, he and Berg helped organise an international meeting of scientists in Washington last December to discuss the ethical implications of the tool. “It’s not ready for prime time now, but it’s only years off,” he says. “We should be thinking about it.”