He Jianhui, a scientist at the Southern University of Science and Technology in Shenzhen, believes he has altered the DNA of twin girls to stop them being infected in the future. The scientist claimed he altered seven couples’ embryos during fertility treatments, with one pregnancy resulting. All of the men in the Chinese boffin’s experiment had HIV and the women did not.
The twin girls were born a few weeks ago.
Mr He says he was able to neutralise a gene called CCR5, which forms a protein doorway that enables HIV to enter a cell.
He claims to have altered the twins’ DNA while they were embryos.
But experts say his potentially groundbreaking research has not been independently confirmed.
Similar work is banned in most countries.
Mr He said he changed embryos for seven couples undergoing IVF treatment.
He said: “I feel a strong responsibility that it’s not just to make a first, but also make it an example.
“Society will decide what to do next.”
His work has not been published in a journal to be examined by other scientists.
Mainstream scienstists have rounded on his claims, with the University of Pennsylvania’s Dr Kiran Musunur branding it “unconscionable … an experiment on human beings that is not morally or ethically defensible”.
Julian Savulescu, a professor of practical ethics at the University of Oxford, said: “If true, this experiment is monstrous.
“The embryos were healthy. No known diseases. Gene editing itself is experimental and is still associated with off-target mutations, capable of causing genetic problems early and later in life, including the development of cancer.”
Gene editing could potentially stop diseases by removing harmful embryo coding.
Experts fear altering the embryo could cause harm to the individual and future generations.
Scientists are able to carry out gene editing research on embryos have been discarded.