A human chimera is a human with a subset of cells with a distinct genotype than other cells, that is, having genetic chimerism. In contrast, an individual where each cell contains genetic material from a human and an animal is called a human–animal hybrid, while an organism that contains a mixture of human and non-human cells would be a human-animal chimera.[1]
Hybrid embryos are embryos created by mixing human sperm and animal ova, or animal sperm and human ova. Human chimera embryos are human embryos that have had animal cells added to them during early development. … Lastly, transgenic human embryos are human embryos that have had animal genes inserted into them early in development.