The goal of the project is to identify methods for growing organs for human transplants in primates.

Famous Salk Institute researcher Juan Carlos Izpisúa Belmonte, who previously attempted to create human/pig chimeras to investigate their potential for growing organs for human transplant, has more recently succeeded () in creating the first human/monkey chimeras.

The attempt to create human/pig chimeras did not prove successful, due to the significant differences in pig and human cells. Better results had been achieved when the species were similar, particularly mouse/rat chimeras.

So Izpisúa Belmonte teamed up with researchers at Murcia Catholic University (UCAM) in Spain and, to avoid legal restrictions, performed research on human/monkey chimeras in China. This type of research is not currently funded in the United States.

The scientists deactivated genes in monkey embryos required for organ development and then injected human stem cells into the embryos, hoping to see human organs develop within the monkey embryos. The vice-chancellor at UCAM indicated that the initial results were promising, but gave no results.

Many people are concerned about this type of research, particularly with the risk of human stem cells escaping and forming human neurons or sperm cells. The researchers have said they included a built-in self-destruct mechanism in the stem cells if they escape the embryo to prevent just this type of thing from happening.