Many had questions over the transparency of the study, and to what extent the seven sets of parents who took part in the study had full knowledge of what they were doing. He’s answers were short on details, explaining that he had “consulted” scientists in the US and Asia about the clinical trials, but he did not answer directly why he had kept his trials secret from Chinese authorities. When pressed to clarify the process of informed consent, He said that the parents—who were contacted through AIDS support groups—were “very well educated,” but sidestepped a question asking whether his colleagues conducting the trials were trained in taking consent. He added that the informed-consent form was uploaded online for public viewing.

He also did not answer questions of where funding for his trials came from, but said that his private companies were not involved. He said some of the sequencing costs were covered by the university, and that he paid for the medical care and expenses of the participants.

Above all, it seemed the question of the welfare of the twin girls drew the strongest reactions from the crowd. He reassured the audience that he would monitor them for the next 18 years, but did not respond directly to a question about whether their modified genotype would affect their upbringing. He also referred people to an article published on Nov. 26 in the Crispr Journal he co-authored, titled “Draft Ethical Principles for Therapeutic Assisted Reproductive Technologies,” and as further proof of his belief and confidence in his experiment, ended his talk by saying that if the embryo was going to be his baby, he would also undergo the experiment.

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