World’s first case of Gene editing – A Chinese researcher has claimed to develop the world’s first genetically modified human — twin girls whose DNA has been altered with a powerful new tool capable of rewriting the very blueprint of life.
The researcher, He Jiankui of Shenzhen, China, altered embryos for seven couples during fertility treatments, resulting in one pregnancy. The goal was not to prevent or cure any inherited disease but to bestow a trait that is present in few people naturally — an ability to resist possible future infection with HIV, the AIDS virus.
If true, it would be a profound leap in science and ethics.
However, many mainstream scientists have denounced the Chinese report as human experimentation owing to concerns regarding its safety. Some scientists were astounded to hear of the claim and strongly condemned it.
“This kind of gene editing is banned in the United States because the DNA changes can pass to future generations and it risks harming other genes,” said U.S. scientist Michael Deem who was involved in the research. China outlaws human cloning but not specifically gene editing.
He said the parents involved declined to be identified or interviewed, and he would not say where they live or where the work was done.
There is no independent confirmation of His claim, and it has not been published in a journal, where it would be vetted by other experts. He revealed it Monday in Hong Kong to one of the organizers of an international conference on gene editing that is set to begin Tuesday, and earlier in exclusive interviews with The Associated Press.
“I feel a strong responsibility that it’s not just to make a first, but also make it an example,” He told the AP. “Society will decide what to do next” in terms of allowing or forbidding such science.
He, in a video uploaded to his lab’s YouTube channel, detailed the monumental breakthrough in gene editing claiming the twin girls “came into this world as healthy as any other babies” and that the gene editing had worked safely — only editing the CCR5 gene.
In recent years scientists have discovered a relatively easy way to edit genes, the strands of DNA that govern the body. The tool, called CRISPR-cas9, makes it possible to operate on DNA to supply a needed gene or disable one that’s causing problems.
He said he chose to try embryo gene editing for HIV because these infections are a big problem in China. He sought to disable a gene called CCR5 that forms a protein doorway that allows HIV, the virus that causes AIDS, to enter a cell.
All of the men in the project had HIV and all of the women did not, but the gene editing was not aimed at preventing the small risk of transmission, He said. The fathers had their infections deeply suppressed by standard HIV medicines and there are simple ways to keep them from infecting offspring that do not involve altering genes.
Instead, the appeal was to offer couples affected by HIV a chance to have a child that might be protected from a similar fate.
The gene editing occurred during IVF, or lab-dish fertilization. First, sperm was “washed” to separate it from semen, the fluid where HIV can lurk. A single sperm was placed into a single egg to create an embryo. Then the gene editing tool was added.
When the embryos were 3 to 5 days old, a few cells were removed and checked for editing. Couples could choose whether to use edited or unedited embryos for pregnancy attempts. In all, 16 of 22 embryos were edited, and 11 embryos were used in six implant attempts before the twin pregnancy was achieved, He said.
Tests suggest that one twin had both copies of the intended gene-altered and the other twin had just one altered, with no evidence of harm to other genes, He said. People with one copy of the gene can still get HIV, although some very limited research suggests their health might decline more slowly once they do.
Several scientists reviewed materials that He provided to the AP and said tests so far are insufficient to say the editing worked or to rule out harm.
They also noted evidence that the editing was incomplete and that at least one twin appears to be a patchwork of cells with various changes.
The Chinese scientist, He, said he personally made the goals clear and told participants that embryo gene editing has never been tried before and carries risks. He said he also would provide insurance coverage for any children conceived through the project and plans medical follow-up until the children are 18 and longer if they agree once they’re adults.
Further pregnancy attempts are on hold until the safety of this one is analyzed and experts in the field weigh in, but participants were not told in advance that they might not have a chance to try what they signed up for once a “first” was achieved, He acknowledged. Free fertility treatment was part of the deal they were offered.
He sought and received approval for his project from Shenzhen Harmonicare Women’s and Children’s Hospital, which is not one of the four hospitals that He said provided embryos for his research or the pregnancy attempts.