For the first time in history, researchers have succeeded in correcting a genetic defect in an embryo. A significant (and controversial) step in the fight against hereditary diseases.
Research team removes genetic disease from embryos
Researchers from the USA have succeeded for the first time using the new Crispr process to correct a genetic defect in human embryos. The genetic defect was a hereditary thickening of the heart muscle, which was excised using Crispr technology so that the artificially fertilized eggs developed normally in the laboratory. In the end, the embryos only lack one thing – a mother to carry them. But the experts did not go that far. They destroyed the embryos a few days after the tests, they explain in “Nature” magazine.
How did this work? The team led by Shouhkrath Mitalipov of the Oregon Science and Health University in Portland had given sperm from a man with a genetic defect in eggs. Under normal circumstances, the genetic defect would have settled in about half of the embryos, the other half would not have carried it inside. By adding another substance (Crispr) to the egg, which removed exactly this defect, the researchers increased the rate of healthy embryos to almost three quarters. As Mitalipov points out, no other parts of the genetic material were damaged by this.
Is the designer baby coming?
The Mitalipov team is sure that the method used by the researchers will one day be able to prevent thousands of hereditary diseases. What sounds very promising in itself meets with a mixed response. Ethicists criticise the intervention into the human genome, genetic engineers celebrate progress. Should it be possible to cut the genome before birth in a way that suits doctors or parents? And is the examination even serious because it might not be able to keep the promise of salvation? Either way, man intervenes radically in evolution.
If you change an embryo and this change is then passed on through generations, there must be very good reasons for the intervention: “It can only be the last resort,” Heidi Ledford emphasizes to “Nature”. In Germany, such experiments have so far been banned; in the USA, genetically manipulated embryos are not allowed to be carried out. At least not yet.