Russian biologist Denis Rebrikov has announced his intentions to produce further gene-edited babies, ignoring the scientific consensus that this should not be done until an ethical framework is constructed to regulate the science involved. Rebrikov’s plans could occur before the end of the year if he receives approval in time.

Rebrikov, who heads a genome-editing lab at Russia’s largest fertility clinic, says he already has an agreement with an HIV centre to recruit patients who want to conduct the experiment.

Rebrikov has said he would target the same gene as Chinese researcher He Jiankui, CCR5, but offer greater benefits than the previous experiment did. He also said his experiment would be less risky or ethically questionable. Rebrikov intends to disable CCR5, which encodes a protein that lets HIV enter cells, and introduce the embryos into HIV-positive mothers.

Scientists reacted predictably to the news. Jennifer Doudna, a molecular biologist at the University of California Berkeley who pioneered CRISPR-Cas9, said the technology was not yet ready for this type of experiment: “It is not surprising, but it is very disappointing and unsettling.”

To ensure the safety of the experiment, Rebrikov said he is developing a technique to avoid the dangers of CRISPR-Cas9 causing “off-target” mutations which switch off a tumour-suppressor gene. Preliminary findings will allegedly go online within a month, though scientists have remained sceptical about such assurances.

CRISPR edits can lead to other difficult-to-detect deletions or insertions, and mean that the gene may not be properly edited – allowing HIV to still access the cell.

CCR5 also has many functions which are not yet understood, but do offer some benefits, including protection against complications following infection by certain viruses.