Scientists have just achieved a research breakthrough by successfully creating a nearly complete human brain, equivalent to that of a 5-week-old fetus, in the laboratory.

The mini-brains, or organoids, are made from reprogrammed skin cells and are about the size of an eraser attached to the end of a pencil. Scientists hope that these building blocks of active cells and nerve fibers will prove to be a valuable research tool, allowing them to test new drugs or learn about brain disorders such as Alzheimer’s disease without having to rely on animals.

In addition to neurons and their signal-transmitting components such as axons and dendrites, the mini-brain also contained support and immune cells. Notably, it possessed 99% of the genes present in the human embryonic brain, a rudimentary spinal cord, and even the primitive structure of an “eye.”

Successfully created human brain in the laboratory.

The mini, artificial human brain is said to provide a better model for testing drugs and learning about brain diseases than current animal brains. Illustration: Discovery

Professor Rene Anand of Ohio University (USA), who led the research, emphasized: "Not only does it look like a developing brain, but its different cell types also express almost all the genes like a brain. We have been trying for a long time to solve complex brain problems or diseases, which cause severe physical and mental pain. This brain model will give us better and more relevant options than the mouse brain, to test and develop treatments."

To create the replica of the human brain, Professor Anand and his colleagues transformed adult human skin cells into induced pluripotent stem (iPS) cells by editing their genes. The artificial stem cells were then coaxed to develop into different cell types and signaling circuits of the brain.

The team is keeping the full details of the mini-brain development process under wraps, but revealed it involved coaxing stem cells to differentiate into all types of brain tissue.

The mini brains were allowed to develop to the equivalent of 12 weeks in the womb and almost reached the maturity of a 5-week fetal brain.

"If we let it develop to 16 or 20 weeks, the mini brain could be complete and fill in 1% of the missing genes compared to the real fetal brain. We haven't tested that yet," Professor Anand added.

According to Khampha.vn