The following is an editorial summary.
A biological chimera is a single organism with two genetically distinct populations of cells. It could be, for instance, a pig which develops a genetically human pancreas. This is as close as genetics gets to the sort of abominations and amalgamations predicted by fear-mongers, and as such it is an area of extreme contention.
According to the American Association for the Advancement of Science’s ScienceInsider:
Current Japanese national guidelines governing stem cell research allow mixing human and animal material in vitro but forbid in vivo experiments[…] At a meeting on 18 June, the Expert Panel on Bioethics of the Council for Science and Technology Policy, the nation’s highest science advisory body, took a step [toward loosening these restrictions] by recommending that the guidelines be changed.
This comes at the request of stem cell biologist Hiromitsu Nakauchi at the University of Tokyo, who has had success in growing rat pancreases in mice and now wants to pursue the production of a viable human pancreas grown inside a pig. Nakauchi told ScienceInsider “that to the best of his knowledge, he is the first to try this approach to generating human organs.”
Read the full story here: Japan to Relax Ban on Chimeric Embryo Experiments