Chinese Scientists Add Human Genes to Monkey Brains

Earlier this year, scientists in China embarked on an experiment that has caused condemnation from scientists in other parts of the world. Humans have a gene in their brains called MCPH1. It is believed that this gene plays an important role in brain development. More specifically, this gene regulates brain growth in the human fetus. Chinese scientists took some of these human genes and transplanted them into the brains of eleven monkeys.

According to the participating scientists, the purpose of the research was to examine the genetic basis and the evolution of human brains. The monkeys that were used for the experiment are referred to as “transgenic monkeys.” So, what happened to these transgenic monkeys? First of all, it took longer for the brains of these monkeys to fully develop. Their brains took about the same amount of time to develop as does a human baby’s brain, rather than the faster monkey brain development. Basically, this means that the transgenic monkeys stayed in the childhood developmental phase for a longer period than would normally be the case with their species.

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Slower brain development was not the only result of this research. Once the brain development was completed, the monkeys were put through a series of tests to measure their brain function. According to the study, the monkeys apparently became more intelligent due to having the human gene, with their short-term memory improving and their reaction times shortening.

The backlash from this experiment was rather quick to happen. To begin with, six of the original eleven transgenic monkeys died due to the research. This left the scientists with only five monkeys as subjects for their experiment. The project cannot be considered to be “successful” with such a high mortality rate among its subjects. As a result of having such a small sample size, the Chinese scientists can only describe their findings as “preliminary.”

In addition to the small sample size, the experiment has caused some familiar ethical questions to resurface. Animal experiments such as these, with a large percentage of the subjects dying, are considered inhumane. Many scientists feel that tampering with the brains of animals, in particular implanting human brain cells into another species, is unethical and perhaps immoral. One of the scientists from the project has considered having his name removed from the paper.

The scientist who is considering removing his name from the project paper, Martin Styner from the University of North Carolina, had this to say: “Now we have created this animal which is different than it is supposed to be. When we do experiments, we have to have a good understanding of what we are trying to learn, to help society, and that is not the case here.” The Chinese scientists who led the study have defended their experiment. However, Western researchers continue to question the ethics of this study. The paper has not found a publisher in the West.