Scientists working on the frontiers of medicine fear that outrage over registered genera of cut-off children in China could threaten promising research on how to change heredity in order to fight off various disorders.
Researchers are quickly learning how to edit DNA to combat conditions such as Huntington, Tai-Sachs and hereditary heart disease, conduct legitimate experiments in laboratory animals and Petri dishes without making a final decision on the creation of children. Now they are worried about the reaction to their work.
“Palkists, who claimed that scientists would not behave responsibly in the development of the next generation of gene modifications, now have ammunition,” said an embarrassed Kyle Orvig, a reproductive specialist from the University of Pittsburgh, who hopes to eventually change sperm production for infertility treatment.
He said that there is a clear public demand for the research that he is conducting.
A Chinese researcher sent a shock wave through the scientific community this week when he claimed that he changed the DNA of embryos in the hope of making them resistant to the AIDS virus. He reported the birth of twins and said that there may be another pregnancy as a result of his work.
International guidelines for many years have said that editing genes that can change a person’s heredity — through modified eggs, semen, or embryos — should not be tested on human pregnancies until scientists learn if the practice is safe. One fear is that such experiments can inadvertently damage genes, which can then be passed on to future generations.
China ordered that the seemingly underground experiments of He Jiankui and his team stop.
“This is what we fear: not legitimate scientists are crazy people who just try to do it without even worrying about the consequences,” said Shuhrat Mitalipov of the University of Health and Science of Oregon, who conducts laboratory experiments to eliminate gene defects in human embryos.
If, as a result of the protest, more restrictions are added to the current rule of the rules about what can be studied and how, the field "will probably be discarded for decades," he added.
The challenge, said Orwig, is "to convince the community that this is one bad apple, but it does not reflect what most people do."
There are several types of gene editing. Experiments on trying to fix damaged genes in children and adults with diseases such as sickle cell are simple enough, because such a narcotic approach will only affect the patient, not his or her offspring.
Much more controversial is editing germline genes or modifying genes so that they will be passed on through generations. The big ethical question is whether this intervention should be limited to genes that could otherwise cause incurable disorders, or whether medicine should be free to create designer children with certain traits, such as high IQ.
“I really think that the public is probably open to a fairly clear therapeutic use of these kinds of things to prevent the transmission of the disease. But there is significant discomfort, if not complete opposition, to using improvements, ”said Josephine Johnston, an expert on biomedical ethics and politics at the Hastings Center, a research institute for bioethics located in Harrison, New York.
In a survey last summer, the Pew Research Center found that most Americans – about seven out of ten people – said that changing the DNA of an unborn baby to treat a serious illness that the child would otherwise give birth to would be appropriate. But support has plummeted when people have been told that this will be related to research with embryos.
And only 19% believe that editing genes for such things as enhancing intelligence would be appropriate, found Pugh.
How to prove that gene editing is safe enough to legally try to carry out pregnancies in humans is a mystery, said the bioether of the University of Pennsylvania, Jonathan Moreno. “No regulator follows this child throughout his life, and especially his offspring,” he noted.
Another question for ethics: even if it was deemed safe, do you need to edit the genes of embryos that really need today's options? Already, families who can afford expensive in vitro fertilization can pay extra for genetic testing of embryos — and implant only those who are free from known dangerous mutations.
But such a pre-implantation diagnosis is not the answer for everyone, warned Johnston. IVF does not always produce enough embryos to select a pair. And since testing reveals more and more unrest, people need to understand: “there will be no perfect embryo,” she said.
In Pittsburgh, Orvig sees the sperm, suggesting perhaps the more practical first step in germline editing. Some male infertility is caused by genetic defects that prevent egg stem cells from producing sperm correctly. His team is studying barren men to find the genes to be guilty.
Among his plans: stem-stem cells and implant repaired in infertile mice to see if they produce sperm, which leads to healthy infant mice.
This method can be adjusted so that genetic change is not necessarily passed on to the next generation, he said.
Young women who have undergone some cancer treatment can already store ovarian tissue in the hope of a future pregnancy, and Orvig once said that we should remove, say, a mutation in this tissue that could otherwise spread the BRCA mutation to breast cancer.
Meanwhile, careful animal work with sperm could "lay the foundation for how it can be done in humans," he said. “When public attitudes change, and politics changes, we will be ready.”