The Chinese scientist, who claims to have created the first genetically modified children in history on Wednesday, announced a “pause” in his clinical trials after a global controversy unleashed by his statement.
At a medical conference held on Wednesday in Hong Kong in a crowded amphitheater, He Jiankui reiterated that he allowed the birth of twins, whose DNA was modified to make them resistant to the AIDS virus.
He also explained that eight married couples – everything that was formed by a seropositive father and a seronegative mother – volunteered for the trial, but one of them was withdrawn.
"I apologize because the result unexpectedly leaked out," he said in an interview with Jiankui, referring to the videos posted on YouTube on Sunday, in which he announced the birth of twins named Lulu and Nana.
"In connection with the current situation, there is a break in clinical trials," added the scientist who runs the laboratory in Shenzhen.
Announcement of these births caused sharp criticism throughout the world for the act described by many researchers as "madness." In the scientific community, many also condemned the lack of independent verification or the fact that healthy embryos were infected with genetic modifications.
One step back
Some experts believe that such modifications can cause unwanted mutations in areas other than those that have been processed. But he defended his work on Wednesday at the podium and said that parents, volunteers, are well aware of the risks of “side effects” and “decided to implant”.
He also stated that the University of Science and Technology of the South, in the city of Shenzhen, to which it belongs, "was not aware of the process."
The center itself had previously distanced itself from the researcher, stating that he had been out of work since February and had not paid, and said that he was “deeply shocked.”
The conference organizers also stated that they are not aware of his investigations.
The moderator of the round table, Robin Lovell-Badge, for his part suggested that this essay implies a “step backward” for the scientific community.
“This is an example of an approach that was not careful enough and proportionate,” he said. "Nevertheless, it is obvious that this is something historical, these two babies would be the first to be genetically modified, this is the capital moment in history," the moderator added.
Conference president biologist David Baltimore, a Nobel Prize winner, condemned "the lack of self-regulation of the scientific community due to lack of transparency."
A geneticist trained at Stanford University in the United States says he used the CRISPR / Cas9 technique, known as “genome scissors,” which allows you to remove and replace unwanted parts of the genome as you would a typo on computer.
Twins were born, he said, after in vitro fertilization from modified embryos to implantation in the mother’s womb.
This method opens prospects in the field of hereditary diseases. But this is very controversial, because the changes made will be passed on to future generations and may affect the entire genetic heritage.
American researcher from China, Feng Zhang, who claims that paternity CRISPR / Cas9, considered the experiment He dangerous and not necessary. “This experience should not have been made; what he did was not scientific,” he told reporters during the conference.
Chinese Vice Minister of Science and Technology Xu Nanping said on Tuesday, according to public television, that if the twins are alive, it is illegal.
According to the ethical principles published in 2003 for research on embryonic stem cells, in vitro culture is possible, but only for 14 days after fertilization or nuclear transplantation.
According to Qiu Renzon, the pioneer of bioethical problems in China, Chinese researchers often avoid sanctions, as they only have to report to their institution. And some do not foresee sanctions in case of professional absence.
China wants to become a leader in genetic research and cloning, but the gray areas of country legislation sometimes allow for conflicting experiments.