[6] In November 2018, He announced that he had created the first human genetically edited babies,[7][8] twin girls who were born in mid-October 2018 and known by their pseudonyms, Lulu and Nana.

[15] On 30 December 2019, a Chinese district court found He Jiankui guilty of illegal practice of medicine, sentencing him to three years in prison with a fine of 3 million yuan.

[10][22][23] After receiving his doctorate, Michael Deem arranged for He to work on CRISPR/Cas9 gene-editing technique as a postdoc fellow with Stephen Quake at Stanford University.

[25] Responding to an ad, He returned to China in 2012 under the city of Shenzhen's Peacock Plan[25] and opened a lab at the Southern University of Science and Technology (SUSTech).

[26][27] He founded Direct Genomics in 2012 in Shenzhen, to develop single-molecule sequencing devices based on patents invented by Quake that had formerly been licensed by Helicos Biosciences.

[31] In August 2018, He met with Chinese-American doctor John Zhang to discuss plans to launch a company focused on "genetic medical tourism."

[24] In 2017, He gave a presentation at Cold Spring Harbor Laboratory describing work he did at Southern University of Science and Technology (SUSTech), in which he used CRISPR/Cas9 on mice, monkeys, and around 300 human embryos.

[45] Formally presenting the story at the Second International Summit on Human Genome Editing at the University of Hong Kong (HKU) three days later, he said that the twins were born from genetically modified embryos that were made resistant to M-tropic strains of HIV.

[46] His team recruited 8 couples consisting each of HIV-positive father and HIV-negative mother through Beijing-based HIV volunteer group called Baihualin China League.

[9] When they were born, it was unclear if there might be long-term effects from the gene-editing; He was asked about his plans to monitor the children, and pay for their care should any problems arise, and how their confidentiality and that of their parents could remain protected.

[55] In February 2022, Chinese scientists called for building a special facility to care for and study the three children born with genetically edited genomes or 'CRISPR Babies'.

"[58] On 24 November, he wrote: "Gene therapy in Western countries often costs millions of dollars, which makes many families fall into poverty due to illness.

[61] He also said on a microblogging site, Weibo, that he had applied for government funding for a DNA synthesiser project, commenting: "[I will] continue the scientific research and serve the country...

[12][7] It was first made public on 25 November 2018 when Antonio Regalado published a story about the work in MIT Technology Review,[42] based on documents that had been posted earlier that month on the Chinese clinical trials registry.

[64] An eminent bioethicist, Ren-zong Qiu, speaking at the Second International Summit on Human Genome Editing, commented on He's research as "a practice with the least degree of ethical justifiability and acceptability".

[47] Developmental biologist Kathy Niakan of the Francis Crick Institute said, "If true...this would be a highly irresponsible, unethical and dangerous use of genome editing technology.

[64][68] The National Institutes of Health (NIH) of United States announced a statement on 28 November 2018 signed by its Director Francis S. Collins, condemning He and his team for intentionally flouting international ethical norms by doing such irresponsible work, and criticizing that He's "project was largely carried out in secret, the medical necessity for inactivation of CCR5 in these infants is utterly unconvincing, the informed consent process appears highly questionable, and the possibility of damaging off-target effects has not been satisfactorily explored".

[69] The Chinese Academy of Medical Sciences published an announcement in the journal Lancet, stating that they "are opposed to any clinical operation of human embryo genome editing for reproductive purposes in violation of laws, regulations, and ethical norms in the absence of full scientific evaluation", and condemning He for violating relevant ethical regulations and guidelines that have been clearly documented by the Chinese government.

George Church, a geneticist at Harvard University, defended some aspects of the experiment and said gene editing for HIV resistance was "justifiable" since HIV is "a major and growing public health threat", but questioned the decision of this project to allow one of the embryos to be used in a pregnancy attempt, since the use of that embryo suggests that the researchers’ "main emphasis was on testing editing rather than avoiding this disease".

[66][71] Arthur Caplan, bioethicist at the New York University School of Medicine, said that engineering human genes is inevitable and, although there are concerns of creating "designer babies", medical researchers are more interested in using the technology to prevent and treat diseases, much like the type of experiments performed by He.

[15][83] An investigating task force set up by the Guangdong Provincial Health Commission released a preliminary report on January 21, 2019, stated that He Jiankui had defied government bans and conducted the research in the pursuit of personal fame and gain.

The report confirmed that He had recruited eight couples to participate in his experiment, resulting in two pregnancies, one of which gave birth to the gene-edited twin girls in November 2018.

The report further said He had made forged ethical review papers in order to enlist volunteers for the procedure, and had raised his own funds deliberately evading oversight, and organized a team that included some overseas members to carry out the illegal project.

[15] On 30 December 2019, the Shenzhen City Nanshan District People's Court sentenced He Jiankui to three years in prison and fined him 3 million RMB (about US$434,000).