China orders probe into scientist claims of first gene-edited babies

Beijing has ordered an investigation into claims by a Chinese scientist to have created the world's first genetically-edited babies, a move that would be a ground-breaking medical first but which has generated a barrage of criticism.

A video posted on YouTube by university professor He Jiankui said that the twin girls, born a few weeks ago, had had their DNA altered to prevent them from contracting HIV, prompting a heated debate among the scientific community.

As experts cast doubt over the claimed breakthrough and others decried it as a modern form of eugenics, China's National Health Commission ordered an "immediate investigation" into the case, the official Xinhua news agency reported early Tuesday, citing a statement on the NHC's website.

The professor, who was educated at Stanford University in the US and works from a lab in the southern Chinese city of Shenzhen, said the twins' DNA was modified using CRISPR, a technique which allows scientists to remove and replace a strand with pinpoint precision.

He said the babies, known as "Lulu" and "Nana" although they are not their real names, were born through regular IVF but using an egg which was specially modified before being inserted into the womb.

Gene editing is a potential fix for heritable diseases but it is extremely controversial because the changes would be passed down to future generations and could eventually affect the entire gene pool. The MIT Technology Review warned "the technology is ethically charged".