• He Jiankui, the Chinese researcher who stunned the scientific world with his claim of having genetically altered a set of twins born this month, defended his work Wednesday at an international genome editing summit in Hong Kong.
• He’s presentation, however, appears to have done little to allay strong condemnation from other researchers in the field, who charge his work breaches ethical and scientific norms. Scrutiny of He’s research methods has also grown, with China’s National Health Commission requesting an investigation and institutions associated with He disavowing knowledgeof his work.
• Addressing the summit, He said he’s “proud” of his work and pushed back against criticism that the genetic changes made using CRISPR/Cas9 — disabling the CCR5 gene to confer resistance to HIV infection — weren’t medically necessary. He also indicated another pregnancy involving an edited embryo had occurred.

Amid a storm of ethical criticism, the question of whether He accomplished exactly what he claims remains.

At the summit, He presented details of his research, including more information on the genetic sequencing he conducted before and after the birth of the twin girls, named Lulu and Nana.

He also said he submitted his work to a scientific journal for review, but didn’t indicate which one. Conference organizers introducing He at the summit indicated slides submitted by the researcher beforehand did not include mention of implanted human embryos.

The lack of transparency has strengthened accusations that He deliberately conducted his work in secret. Southern University of Science and Technology, where He works, said it had no knowledge of the research and that the work was conducted outside of its grounds.

A statement from the owners of Shenzhen Hospital, where He claimed to have received ethical approval, claims that signatures on an application to the institution’s ethics committee appear to be forged, according to a Bloomberg report.

“Foremost, that edited human babies were generated without the full engagement of independent scientific and ethics experts, relevant regulatory institutions, and governing bodies is appalling,” wrote David Liu, a professor at Harvard University heavily involved in genome editing research, in a statement.

Questions from attendees at the conference centered on how He obtained approval to proceed as well as how he secured informed consent from the participating parents-to-be.

He indicated he reviewed the informed consent process with about four people and said that he had previously consulted with visiting scientists and ethicists in the U.S.

Informed consent, always important, is particularly critical for gene editing studies given the uncertainty and risk for off-target effects and other unintended consequences.

More broadly, He’s study brings forward core ethical questions for the entire gene editing field — questions that will need to be addressed comprehensively and internationally to avoid the potential for catastrophic missteps.