Genetic Editing: Where Do We Draw the Line in Using Animals for Medical Research?

“Primates are highly intelligent and social animals. It is not ethical to deliberately harm them, and especially when the chance of tangible benefit for human patients is so small. Such research is very irresponsible.”

— Andrew Knight, Professor, Animal Welfare & Ethics, University of Winchester

The first primate clones, macaque monkeys, occurred early in 2018 in China. Chinese researchers have now successfully repeated this process, cloning five gene-edited macaque monkeys, using the same somatic cell nuclear transfer method. But these monkeys were cloned from a primate whose genome was edited using CRISPR-Cas9 to get rid of a gene that is important in determining circadian rhythm.

The scientists altered a number of fertilized monkey embryos in a way that resulted in circadian sleep disorders, a disorder with known serious mood and physical effects. The researchers then selected the animal with most severe disease characteristics to clone. A statement was made announcing the success and an expectation that populations of customized gene-edited macaque monkeys with uniform genetic background for specific diseases and conditions will soon be available for biomedical research.