The controversy of Chinese twins Lulu and Nana resistant to HIV
Scientists claim that the gene-editing done on Chinese twins to immunize them against HIV might have failed and created undesirable mutations.
MIT Technology review had released snippets from the publication by Chinese biophysicist He Jiankui explaining how he ignored scientific and ethical norms to create the twins Lulu and Nana, who were born in 2018.
It was not clear whether the extensive claim by He Jiankui about the innovation to “control HIV epidemic” had been successful. He Jiankui and his team tried to immunize the babies against HIV, but the scientific world was in doubt as the team could not reproduce the gene mutation that induced the resistance.
CCR5 is a co-receptor in cells used by HIV to enter and infect host cells. A few individuals have an inborn CCR5 mutation in their genome that makes them resistant against HIV infection. He Jiankui targeted this gene using CRISPR, the most promising innovation that had been accelerating research since 2012.
Fyodor Urnov, a scientist at the University of California, says that the Chinese scientist’s claim that they produced the powerful CCR5 mutant is a deliberate misrepresentation of actual data. According to Fyodor, the data shows that they have failed to reproduce the CCR5 mutant and the Chinese twins resistant to HIV is just a deliberate falsehood.
The team targeted the right gene but did not replicate the Delta32 variation, instead replicated on some novel genes whose effects are unclear to date.
CRISPR is still an unreliable tool for genome editing due to its off-target editing, and using it in humans is highly unethical and controversial. The Chinese scientists’ statement that they had scanned for off-target edits in the embryo and could find only one. Fyodor is confident that such a comprehensive scanning of each cell in the embryo is impossible without eventually destroying them.
Jeanne O’Brien, a reproductive endocrinologist, told the MIT Technology Review that the parents’ lack of access to fertility treatment might have forced them to take part in such an experiment in spite of the huge risks to their children.
In China, there is a social stigma towards HIV patients, which would have made the HIV positive father impossible to reach out to fertility treatment even though a well-established technique “sperm washing” prevents the infection from passing on to the children.
The authors of the Chinese publication have also made sure that its impossible to track the parents like leaving the names of the fertility doctors off the paper and date of birth that varies in different reports.
Author: Namitha Thampi
Editor’s Note; Chinese twins resistant to HIV, deliberate falsehood, misinterpretation of actual data