He Jiankui, a Stanford University alumnus, now working at a laboratory in Shenzhen, made the announcement on Wednesday on the fringes of an global conference in Hong Kong.
"I must apologize, this result was leaked unexpectedly", He Jiankui told a Hong Kong medical conference on Wednesday, as cited by AFP.
Germline gene-editing refers to genetic changes in every cell, that will be passed on to future generations.
Nobel laureate David Baltimore said professor He's work would "be considered irresponsible" because it did not meet criteria many scientists agreed on several years ago before gene editing could be considered.
He has said his goal wasn't to cure or prevent an inherited disease but to try to bestow a trait that few people naturally have - an ability to resist possible future infection with HIV, the AIDS virus.
In Hong Kong, Organisers of the Second International Summit on Human Genome Editing denounced He's "unexpected and deeply disturbing" claim that human embryos had been edited and implanted, and called for closer supervision of the field at the conclusion of the conference Thursday. Then university has said it wasn't involved in the study, though documents available online about the work included the name of the institution.More news: 145 pilot whales die after stranding on New Zealand beach
In a statement published Monday, the conference organizing committee said genome editing trials should be conducted "only for compelling medical reasons in the absence of reasonable alternatives, and with maximum transparency and strict oversight".
"How can a scientific experiment with so many uncertainties be kept as a secret for such a long time?"
The China Association for Science and Technology (CAST), a research society mainly comprised of researchers and scientists, said He Jiankui's candidacy of an award for young scientists will be disqualified, as CAST adopts a "zero tolerance" attitude to those who breach scientific ethics and norms. They say there are serious unanswered questions about the safety of embryo editing and a need to make sure that such research is conducted in a transparent, monitored way so the technology is not misused.
Chinese Vice Minister of Science and Technology Xu Nanping told state broadcaster CCTV that his ministry is strongly opposed to the efforts that reportedly produced twin girls born earlier this month.
The Guangdong province Health Commission said on its website on Wednesday it and Shenzhen city had set up a team to investigate the case. Although his appearance had been previously scheduled, Lovell-Badge said He had earlier "sent me the slides he was going to show in this presentation and it didn't include anything that he is going to talk about today". Using gene-editing tool CRISPR, the team was able to switch off the HIV-related gene on embryos during IVF treatment.
He, who was educated at Stanford University, said the twins' DNA was modified using CRISPR, a technique which allows scientists to remove and replace a strand with pinpoint precision. As scientists from around the world voiced their criticism, the Chinese government ordered an immediate investigation into He's claims.