Study Finds Human Brain Develops From Two Distinct Cell Lineages
A new study by Stanford Medicine has challenged the traditional understanding of how the human brain develops, finding that its front and back regions originate from two distinct types of progenitor cells during embryonic development.
Published in Nature Neuroscience, the research suggests that different parts of the brain follow separate developmental pathways before forming the complex organ found in humans.
Two Cell Types Shape Different Brain Regions
Researchers found that one group of progenitor cells expresses the Otx2 gene and develops into the forebrain and midbrain. These regions are associated with functions including language, consciousness and abstract reasoning.
A separate group of cells expressing the Gbx2 gene develops into the hindbrain. This part of the brain controls several essential automatic functions, including breathing, heartbeat and sleep.
Senior study author Kyle Loh said the research provides the first evidence that the front and back portions of the human brain originate from completely different progenitor cell populations.
Different Developmental Pathways
The researchers discovered that the two cell populations do not overlap and have distinct chromatin structures, which help keep them on separate developmental paths.
The finding may also explain why researchers have faced difficulties producing hindbrain neurons in laboratory settings.
Using the new understanding of brain development, the team successfully converted human pluripotent stem cells into functional hindbrain motor neurons for the first time.
Potential Benefits for Disease Research
The development could provide scientists with a new tool for studying neurological diseases that affect hindbrain motor neurons.
These include spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS), conditions that can damage neurons involved in important functions such as swallowing and breathing.
Researchers believe the findings could eventually contribute to the development of regenerative treatments for neurodegenerative disorders.
Evolutionary Evidence
The researchers also observed a similar developmental pattern in chickens, zebrafish and acorn worms.
According to the study, the pattern may date back at least 550 million years, suggesting that the separation between these developmental pathways has deep evolutionary roots.
Scientists say the discovery could help advance research into brain development and potentially support future approaches to treating neurological diseases.
