Aggregated News
The federal government announced plans Thursday to lift a moratorium on funding of certain controversial experiments that use human stem cells to create animal embryos that are partly human.
The National Institutes of Health is proposing a new policy to permit scientists to get federal money to make embryos, known as chimeras, under certain carefully monitored conditions.
The NIH imposed a moratorium on funding these experiments in September because they could raise ethical concerns.
One issue is that scientists might inadvertently create animals that have partly human brains, endowing them with some semblance of human consciousness or human thinking abilities. Another is that they could develop into animals with human sperm and eggs and breed, producing human embryos or fetuses inside animals or hybrid creatures.
But scientists have argued that they could take steps to prevent those outcomes and that the embryos provide invaluable tools for medical research.
For example, scientists hope to use the embryos to create animal models of human diseases, which could lead to new ways to prevent and treat illnesses. Researchers also hope...