June 2, 2023

IVF expert backs rabbit-human embryos

Professor Alan Trounson wants to create rabbit-human hybrids

Leading reproductive biologist Alan Trounson, of Monash University in Melbourne, says that hybrid rabbit-human embryos could be a useful source of embryonic stem cells to test drugs for incurable diseases like cancer, Alzheimer’s and multiple sclerosis. Addressing a conference in Melbourne, he said that interspecies embryos would be used in research centres around the world, if not in Australia, within the next two to four years.

With a review of Australia’s two-year-old law governing embryo research and cloning coming up, Professor Trounson wants Parliament to put human-animal hybrids (or chimaeras) on the agenda as well. Under current legislation they are banned, although he recently described them as “a new and exciting area of potential medical research” in an op-ed piece in The Australian.

Some progress has already been made in the creation of chimaeras. Scientists at a Shanghai laboratory announced last year that they had developed 400 cross-species embryos, with 100 of them growing to the blastocyst stage. They emptied rabbit eggs of their nuclei and replaced them with nuclei from human cells, effectively creating beings which had human chromosomes and rabbit mothers.

At the time, many scientists were sceptical of the results, although there was little criticism of the experiment on ethical grounds from scientists in the field. Professor Trounson believes that these embryos like these could not develop into a human being, but that they could be useful for testing drugs. This technique “overcomes the need for large numbers of human eggs for therapeutic cloning,” he said. “By using rabbit eggs, we could obtain stem cells that would enable us to screen drugs that may be able to control or reverse serious diseases like Alzheimer’s.”

Professor Trounson made other predictions about the future of reproductive technology. Couples will be selecting embryos to give their children a lower risk of cancer and diabetes. Using cloning techniques, scientists will be able to create artificial sperm and eggs. And the reproductive age of women could be extended by 20 years.

“We need to have some public discussion but my feeling is that the demand is there for women to have babies in their 40s and 50s when they would normally find it very hard, if not impossible, to become pregnant,” he said. “I don’t think anyone wants to see women in their late 60s or 70s having babies because there would be risks to both them and the children. But women in their 50s tend to be healthier now and could easily bring up a child without any difficulties.”