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Gene-editing: Scientists say experiment may have created ‘unintended mutations’

por Juan Bueno·Diciembre 05, 2019 02:10
Scientists enraged by China's experiment on babies

Scientists enraged by China's experiment on babies

The MIT Technology Review published portions of two previously unseen research papers on Tuesday, principally authored by Chinese biophysicist He Jiankui, who a year ago attempted to use CRISPR DNA editing technology to immunize twins - Lulu and Nana - against HIV.

In November 2018, biophysicist He Jiankui told the world that he had successfully edited the genes of two newborn twin girls, named Lulu and Nana, modifying their CCR5 gene to make them resistant to HIV.

But on December 3, the MIT Technology Review published excerpts from He's manuscripts - titled "Birth of Twins After Genome Editing for HIV Resistance - which he had been trying to get published in journals such as Nature and JAMA". There is only a small percent of people who are born with immunity because of a mutation in a gene called CCR5.

"The claim they have reproduced the prevalent CCR5 variant is a blatant misrepresentation of the actual data and can only be described by one term: a deliberate falsehood", said Fyodor Urnov, a scientist at the University of California, Berkeley. "The statement that embryo editing will help millions is equal parts delusional and outrageous, and is akin to saying that the 1969 moonwalk "brings hopes to millions of human beings seeking to live on the moon". However, while they intended the edits to confer HIV resistance, it could not be certain, since the edits are only similar and not identical to the naturally occurring delta 32 mutation. "Instead, the embryos/eventual babies got novel variations, whose effects are not clear".

Moreover, CRISPR remains an imperfect tool because it can lead to unwanted or "off-target" edits, making its use in humans hugely controversial. Right here, the researchers claimed to have looked for such results within the early-stage embryos and located only one - nonetheless it might be unimaginable to hold out a complete search with out inspecting every of the embryo's cells, and thus destroying it.

The scientists believe that the parents of the twins wanted to partake in this experiment for the wrong reasons.

Lula and Nana's father tested positive for HIV, which carries a lot of social stigma in China. "Was this couple free from undue coercion?"

The authors also appeared to have taken steps to make it hard to find the family, like leaving the names of the fertility doctors off the paper, and including a false date of birth (Hu claimed November 2018 while multiple reports have indicated it was in fact October 2018).

Chinese scientist is facing backlash from fellow scholars for his inhumane experiment on twins.

Dr He's manuscript was submitted to journals including Nature and the Journal of the American Medical Association, but has not been officially published.