Scientists at Duke University have successfully isolated a gene sequence that is integral to human brain development and used it to grow a mouse embryo with a bigger brain.
This is considered quite an accomplishment, as many others have tried and failed at this experiment. The team started the process by identifying the 106 short bits of “enhancer” or gene controlling DNA that were significantly different in human and chimpanzee genomes.
They then chose to test the sequence called HARE5 based on its close proximity to and even direct contact with a well-known pathway involved in early brain development.
HARE5 from humans and chimpanzees were implanted into mouse embryos, and the brains of the human-enhanced specimens grew to be 12 percent bigger than their chimp counterparts.
An integrated reporter gene, which turned the affected areas blue, showed the most change in the neocortex which contains the higher level functions of language and reasoning. The findings provide further insight into the uniqueness of the human brain.
The research also continues to explore the neurological differences between human and chimpanzee brains, especially in relation to fighting human diseases, as chimps do not develop conditions like autism and Alzheimer’s.