Scientists at Columbia's Zuckerman Institute have uncovered a human-specific gene, SRGAP2, that dramatically slows the development of microglia—key immune cells in the brain—over several years, a process much longer than in other mammals. This finding offers fresh insight into how the human brain achieves its remarkable complexity.
- Human microglia take 4 to 8 years to mature, compared to weeks in mice.
- The gene SRGAP2 is more active in microglia than previously recognized.
- Slow brain cell maturation may support higher cognitive functions.
What happened
Researchers at Columbia’s Zuckerman Institute studied the development of microglia, the brain’s primary immune cells, and discovered that these cells mature much more slowly in humans than in mice. While microglia in mice mature in just a few weeks, human microglia take four to eight years to fully develop. This prolonged maturation coincides with the extended development of neurons in the human brain.
Central to this discovery is the gene SRGAP2, which is present in multiple copies exclusive to humans. Earlier research had shown this gene’s influence on the slow maturation of neuronal synapses. The new findings reveal that SRGAP2 is nearly 10 times more abundant in microglia, suggesting it plays a major role in controlling the slow developmental timing of these immune cells as well.
Why it feels good
The extended development period in human microglia and neurons contributes to what scientists call neoteny — the retention of juvenile features over time — which is thought to underlie the extraordinary cognitive abilities of humans. Slow maturation allows for a denser and more adaptable network of neuronal connections, critical for learning, memory, and complex brain functions.
Understanding how SRGAP2 synchronizes the development of multiple brain cell types sheds new light on what makes the human brain unique. These findings not only deepen our grasp of brain evolution but also open new avenues for exploring how disruptions in microglial function might contribute to neurodevelopmental and neurodegenerative disorders.
What to enjoy or watch next
Future research will investigate precisely how SRGAP2 modulates microglia and other brain cells to coordinate the human brain’s extended growth timeline. Scientists aim to uncover more about the gene’s role in brain health and its potential links to diseases.
For those interested in brain science and evolution, follow developments from the Zuckerman Institute and similar research centers exploring the interplay of genetics and brain cell development. Their work promises exciting insights into human neuroscience and the biological roots of cognition.