Human Genes Used to Make Mice Smarter
Most of us have seen some pretty crazy stuff in fiction. From genetically modified raccoons (Guardians of the Galaxy) to dinosaurs created from DNA found in amber (Jurassic Park), you could say that the human imagination is quite expansive when predicting what science may soon be able to do. But what scientists have now done is almost as strange as these fictional exploits of biologists. Teams of researchers in Germany, California, and New York are all experimenting with the same thing, and that thing is the injection of human brain cells into mice. Various experiments are meant to prove different things, but they definitely prove that science is every bit as ambitious as fiction makes it out to be.
Inserting Glial Cells Into The Brain of a Mouse
In Rochester, New York, Steve Goldman and his team of researchers set about to prove that the Glial cells, long regarded as ‘stuffing’ and support for the brain, actually do something. Previously, he inserted fully grown Glial cells into an adult mouse, and watched as their intelligence and memory leapt off the charts. Then, he experimented with mouse pups, using immature glial cells from donated human fetuses. Each mouse pup received 300,000 immature glial cells, which, inside of the mouse brain, quickly matured and took over for the mouse glial cells, multiplying to some 12 million, and completely replacing the native cells. Adult mice who had received this transfusion exhibited a memory capacity of about 4 times that of an ordinary mouse.
The study proves that not only do glial cells facilitate and strengthen the synapse connections between neurons, they also play an important part in memory and cognitive thinking. Human glial cells, called astrocytes are about 10-20 times larger than those in a mouse, and typically contain a great deal more tendrils, which helps to coordinate neural signals. It also proves that while biologists have long considered glial cells to be inferior to neurons, recent data showing that to be false is correct.
The human FoxP2 gene has long been linked with language learning skills, but Wolfgang Enard of the Max Planck Institute for Evolutionary Anthropology in Leipzig Germany found that by inserting the gene into mice, he could increase their learning capacity and learning speed. FoxP2 has been linked to learning languages, and in mutations of the gene, language difficulties, and language comprehension. The study showed that mice with the gene were more likely to remember landmarks, more likely to look around and remember placement in a room in order to get through a maze, and more likely to excel in more than one type of learning.
Most of us would agree that we don’t really want humanized mice running around in the wild any time soon. In fact, scientists agree, putting smarter mice in the wild would be bad for everyone. The mice in the trials are used only in captivity, and only used to test the capacity of the human brain and how it’s various cells affect intelligence. While we can’t except a real life Stuart Little anytime soon, the study is allowing us to understand how brain matter like the FoxP2 gene and glial cells actually affect our intelligence, learning, and memory.