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Children's genetic material would have been adapted by CRISPR.
Already in 2015, Chinese researchers – much to the indignation of the scientific community – were using CRISPR for the first time to adapt the genetic material of human embryos. And now, Chinese researchers have gone further, as this paper suggests, on the CHICTR website: a database in which all clinical studies conducted in China are recorded. The paper says that researcher He Jiankui, who works at the Chinese university Sustech, intends to modify the genetic material of human embryos. And then put those fitted embryos back into the uterus and have them become genetically modified babies.
What is CRISPR?
CRISPR / Cas9 or CRISPR for short is one of the newest and most promising gene therapies. With this therapy, it is possible to adjust the DNA in cells at very specific locations. Specific genes can be turned off or unwanted pieces of DNA replaced by another piece of DNA. In a sense, we need gene therapy for bacteria that uses the CRISPR-Cas system to protect against viruses. It goes like this: as soon as a virus (bacteriophage) enters a bacterium, this one transforms the virus's DNA into a special DNA sequence called CRISPR (Short palindromic repeats in regular clusters and regularly spaced). The bacterium then makes an RNA containing a copy of the virus's DNA. This RNA is taken up by an enzyme called Cas (an abbreviation for CRISPR-associated proteins). These enzymes can be transported in the virus by RNA (also called guide RNA). Once Cas has arrived at the virus, the enzyme cuts the virus's DNA into pieces, so that it can no longer multiply. When researchers apply this gene therapy, they use these enzymes to cut (guided by the guide RNA) into a specific piece of DNA. Once the enzyme has cut a specific DNA fragment, the cell in which the DNA is found is trying to repair that DNA. But often, it happens badly and mutations occur so that the gene consisting of this DNA no longer works. For example, CRISPR / Cas9 can be used to disable specific genes. In addition, it is also possible, in the same way, to replace the "bad" DNA. In this case, you give the RNA template another piece of DNA that, once the enzyme has cleaved the DNA, can be inserted there.
HIV
The document reveals that for his clinical research he is looking for married Chinese couples whose husbands are HIV-positive. Men have to give sperm, which is then used to fertilize an egg of their partner. The embryos created in this way are then adjusted, with particular emphasis on the CCR5 gene. Previous studies have shown that mutations of this gene can guarantee the immunity of people, for example against HIV. And that's exactly what Chinese researchers are looking for, as we read in the document. "By adapting the CCR5 gene to human embryos (…), we want to bring to the world healthy children who can not get HIV." According to Chinese researchers, it is necessary to eliminate HIV and AIDS from the world. "To date, there is no effective drug or clinical technique to completely cure AIDS," they write in the paper. "Fortunately, governments and scientists around the world have devoted a lot of energy to HIV prevention and treatment, but we are still a long way from the goals that the World Health Organization and the World Health Organization have in place. health is set for HIV by 2020. "
Is this so far?
Up to now, this may seem to be only a project. But there is every reason to believe that Chinese researchers have implemented these plans. In the meantime, they have linked their clinical research project to a second document that seems to suggest that there are already 24-week-old pregnant women with a genetically modified child. And in an interview with The Associated Press He even claims that there are already genetically modified twins in the world. Whether true or not, it is unfortunately not verifiable. It is also unclear whether CRISPR has had the desired effect.
Discussion
The use of CRISPR has been the subject of much discussion in recent years. And most researchers agree that the genome editing technique is still in its infancy and that it is not suitable for adapting human life. For example, CRISPR security information is still insufficient. For example, recent research suggests that the genome editing technique causes greater genetic damage than expected in cells. This damage would occur further from where the genetic material was changed. What are the consequences (long term)? "It is important for anyone wishing to use this technology to proceed with caution and carefully consider any potential adverse effects," concluded the researchers who discovered these genetic damage.
Ethically, of course, there are also the necessary hooks and eyes. Because if CRISPR is safe and effective, where do you go to adjust the genetic material of people? Can we go to a world full of designer babies, where parents can provide a list of desired traits and researchers can then tailor an embryo for their future child to meet the criteria? Scientists prefer to use this technique for other purposes. For example, treat and prevent serious (genetic) disorders that can not be treated or prevented otherwise. What approach is it meets these criteria: it is a topic of discussion. People infected with HIV do not always have an HIV-infected child. There are already several ways to ensure that their offspring do not inherit the infection. In addition, it should be noted that its primary purpose is also not to protect children from the infection of their parents: it wishes to make them immune to HIV in general. And this is unpleasant, according to Ainsley Newson, an expert in bioethics at the University of Sydney and not involved in Chinese studies. "We do not need genomic editing to prevent HIV.We need to make existing preventative measures and treatments more widely available." 39, healthy embryos to reduce the risk of contracting HIV is unnecessary or inappropriate. "
Moreover, all this occurs at a stage where we still know little about the effects of the disease. used the CRISPR method on human life in the long run. The question of whether the benefits of this approach outweigh the costs seems appropriate. But no one can answer this question correctly for lack of information, partly because the technology is still in its infancy and partly because of the reluctance with which Chinese researchers communicate about their work. "The tools for adjusting the genes are excellent, but we are still not able to control them enough and to ensure that they can be used safely and effectively among people," said Yalda Jamshidi, associate at St. George's University in London and not involved in Chinese research. "We know very little about the long-term effects and most people would agree that doing experiments on people to prevent a preventable disease only increases our knowledge ( on technology, etc.) Morally and ethically considered unacceptable. "
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