[pazimzadeh]

Why not? Is it ethical to breed dogs for a particular trait? At least in this case it's done to further knowledge.

Pigs are already being genetically humanized in order to enable pig to human organ transplant:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5287079/

https://www.sciencemag.org/news/2017/09/scientists-grow-bull...