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Report: Scientists in China Lost Track of CRISPR Patients Edited by Genes



Gene therapy is very much in the early stages of their development, so it makes sense to monitor patients whose DNA has been modified through innovative CRISPR techniques. However, for some scientists in China, this does not seem a priority.

The Wall Street Journal reported that a number of unknown Chinese cancer patients who had undergone experimental gene therapy were not tracked as well as expected. In this case, patients modified their genes with the CRISPR-Cas9 gene editing tool in an effort to treat their cancer. Scientists responsible for at least one trial failed to maintain contact with their patients afterwards and carry out further examinations, according to the WSJ.

Indeed, follow-up is very important for patients undergoing gene therapy. Changes in DNA can trigger unwanted consequences known as artificial effects. Unexpected health problems that come from gene modification, such as autoimmune disorders, can appear later on.

"Because we don't fully understand the human genome and are still developing knowledge about [CRISPR-Cas9 and related technologies], we need to monitor the intended and unwanted consequences for the life of the patient, "Jennifer Doudna, a biochemist at the University of California, Berkeley, and one of the inventors of CRISPR, told the WSJ.

This is the latest disruptive development for biomedical research in China. Last month, Chinese scientist He Jiankui claimed to have produced the world's first gene-edited baby. The scientist, who works at the South University of Science and Technology in Shenzhen, said he used CRISPR to modify human embryo DNA, which resulted in the birth of twin girls with clear immunity to HIV. Shortly after the news broke, the Chinese government expanded its social credit system to include violations committed by researchers, an attempt to curb endemic scientific errors.

Editing germline genes in humans and implantation of embryos into a mother's womb is not yet legal in China or elsewhere in this regard, largely because gene editing is still in its infancy and because the modified properties will be inherited (both in the US and US). China, may modify the embryo, but must be destroyed after a few days). Somatic gene editing, on the other hand, where the DNA of a living person is changed to treat various diseases, from cancer to hemophilia, produces genetic changes that are not inherited. But somatic gene therapy, such as the germline variety, is also still in its infancy, requiring due diligence, responsible supervision, and great care.

Somatic gene therapy is legal in China and the United States. In the U.S., research scientists have stepped carefully and hesitantly in this direction, with the Food and Drug Association maintaining supervision. Until now, only one gene therapy has been approved in the U.S. – a clinical trial at the University of Pennsylvania to test the safety of CRISPR and involve only 18 patients.


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In China, however, there is nothing equivalent to the FDA. Doctors can proceed with clinical trials after receiving approval from their hospital ethics council, reports the WSJ. In January 2018, at least 86 patients in China had DNA edited with CRISPR. Most of these trials were carried out by Anhui Kedgene Biotechnology Co., a private startup, as WSJ pointed out:

One Kedgene project has lost contact with a patient whose DNA has been changed, according to someone familiar with the problem. Kedgene founder Mandy Zhou said one experiment did not complete the study as planned, and as a result lost contact with patients. No patients died during treatment in the trial, he added.

Another Kedgene trial, at Anhui Provincial Hospital, treated 18 patients, according to Wang Yong, who ran it. Many participants die when their cancer grows, Dr. Wang, without giving a certain number. Wang said he was asked by the science ministry this month to send a report on the trial, the first time authorities in Beijing had sought information about it since it began more than a year ago.

Three of the doctors involved in gene editing trials were recently contacted by the Chinese ministry of science and health (the closest thing China has with the FDA, which is not even really close). When the WSJ contacted these ministries for more information, they declined to comment.

This is all very frustrating and regrettable, mostly because this sad scientific behavior gives CRISPR a bad name and the whole prospect of editing genes. CRISPR and other gene editing technologies are ready to eliminate a number of diseases, and even usher in the age of selection and enhancement of human nature (twins edited genes with immunity to the AIDS virus, for example, are actually very good ideas in principle – this is too premature).

Unfortunately, the situation with Chinese scientists can influence public opinion on this promising biotechnology, which has become controversial.

[The Wall Street Journal]

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