In September 2005, the dedication of public financial aid by the National Health Institutes for experiments on transferring human stem cells to animal embryos to produce chimeras was banned. However, on 4 August this year, this ban was lifted for certain experiments, and it was proposed that a panel of experts be created to evaluate the ethical problems with chimeras production.
The ban also prohibits the transfer of human stem cells before the nervous system begins to form in the recipient animal embryo, a measure aimed at limiting the implantation of human stem cells in the brain of the transplanted animal.
Chimeras are currently being used to study the early stages of embryonic development and various human diseases, although the main aim is undoubtedly to produce animals with human organs for human transplants (Nature, 536; 135, 2016). This regulation is expected to be applied from January 2017.
We have already referred to these practices (see HERE) which, from a bioethical perspective, can be labelled as clearly utilitarian.