China: First genetically modified babies ?: Newborns carry a gene against HIV, edited with the CRISPR gene

The CRISPR / Cas9 gene from the claw has given doctors new ways to edit the human genome. Because genetic defects can be repaired or targeted genes can be inserted. Until now, however, most of these gene therapies have been in animals, including Duchenne muscular dystrophy and loss of genetic hearing. In human cell cultures, genetic abnormalities of sickle cell disease and an Alzheimer's mutation have been repaired.

But all these interventions have one thing in common: if they are used in humans, they only correct the defects of the respective patients. Since the germ cells of sperm and affected oocytes still carry the genetic defect, their offspring may continue to inherit the defect and become ill.

Possibility of germinal therapy or taboo?

It would be different with a germ line therapy, a gene repair, which is performed in the fertilized egg: because of this, develop all the later cells of the man, also transmit to his germ cells the modified gene code and pbad it on to all descendants. Such an intervention therefore modifies the genetic material of all future generations and is therefore very controversial.

"We are working on the operating system of a human being," said Eric Zopol of the Scripps Research Institute in California, in front of the Associated Press (AP). Due to the immaterial and permanent consequences and ethical concerns badociated with such technology, these manipulations have been banned in Germany and many other countries. In the United States, researchers can perform such genetic modifications on embryos, provided that they do not produce a viable fetus.

Experimental domain China

It's different in China. Among other things, the researchers have already performed many interventions on the germline with CRISPR / Case 9. For example, one team repaired the genetic defect at the origin of thalbademia, a hereditary blood disease, and a Another injected a variant of the gene into the genome of an embryo, which then had to protect it from infection with HIV. This mutation of the CCR5 gene prevents the IH virus from entering the cell.

Exactly, this intervention should have been performed in two newborn twin girls. He Jiankui of the Southern University in Shenzen and his team said he inserted the CCR5 gene variant into fertilized oocytes during artificial insemination using gene scissors. Overall, this mutation of the gene should have been performed in 16 embryos of seven pairs. However, in only one case, the implantation of these engendered embryos resulted in the birth of twins.

So-called healthy born twins

"The two girls Lulu and Nana are born screaming and are as healthy as any other baby," He Jiankui said in a video. According to his data, genetic tests showed that both variants of the CCR5 gene had been successfully replaced in one of the two neonates. In the second child, only one of the two alleles is replaced, but in both cases, nothing indicates that changes have been made to other segments of the DNA or other unwanted side effects.

However, scientists doubt that the AP agency has provided data obtained in China for the review. As a result, the tests performed are not sufficient to prove success or exclude damage. They also found evidence that at least one Gemen gene change is incomplete and not available in all cells.

Unpredictable consequences for the child

It is precisely for this reason that Kiran Musunuru of the University of Pennsylvania, for example, believes that it is unethical to implant and carry out this embryo: "This child has gained almost nothing in terms of protection against HIV, and he takes all the unknown risks.Technology ", criticized the researchers. Recent studies indicate that the CRIPR / Cas 9 gene of the scissors gene triggers undesirable mutations in the genome and increases the risk of cancer, even immune reactions are apparently possible.

Moreover, this intrusion into the genetic material is very controversial, even for perfect medical reasons. Because people with modified CCR5 genes are better protected against HIV infection, but this variant of the gene is more susceptible to other viruses such as influenza or West Nile virus. "It is an unscrupulous and humane experience, which is neither morally nor ethically justified," Musunuru criticizes.

"A big collapse for science"

The chairman of the German Council of Ethics, Peter Dabrock, considers that this forerunner of Chinese researchers is equally critical: "It was true that a baby genetically modified with CRISPR had been produced it would be a great collapse for science, "says the theologian. "Systematically manipulating the biological foundation of human beings is a problem of humanity, but it also shows that it is not enough for science to adhere to codes of conduct that no one believes in."

Tomorrow, an international summit on the communication of the human genitive will begin in Hong Kong, which will include the current state of technology, but also ethical and moral issues. The day He Jianku announces the first birth of baby babies just the day before this conference, Dabrock is considered an affront: "Here, we do not respect the internationally recognized standards within the scientific community," he says. .

It remains to be seen how this will continue and what will be the consequences of the Chinese initiative on the future regulation of germline therapies. Whatever the case may be, He Jiankui and his team must publish their complete data anyway, so that their complete claims can also be verified.