Researchers at Columbia University’s Zuckerman Institute have identified a human-specific gene, SRGAP2, which appears to play a crucial role in the extended maturation period of human microglia, the brain’s most abundant immune cells. The study, published in Neuron, reveals that human microglia mature significantly more slowly than their counterparts in other animals, a process potentially linked to the development of advanced cognitive abilities unique to humans.

The Polleux lab, which has studied SRGAP2 for over 15 years, previously found that this gene increases synaptic density and slows synaptic maturation in human neurons. The new research unexpectedly discovered that SRGAP2 is nearly 10 times more active in human microglia than in neurons. Experiments using both mice and human cells demonstrated that human-specific copies of SRGAP2 dramatically prolong the maturation of human microglia, which takes approximately four to eight years, compared to about three weeks in mice. This extended developmental timeline may help synchronize the maturation of neurons and microglia, contributing to the neotenic (prolonged developmental) characteristics of the human brain thought to underpin its enhanced cognitive capacities.

The findings suggest that SRGAP2 may coordinate the slow developmental pace across multiple brain cell types, including neurons and microglia. The researchers aim to further investigate how this gene promotes neoteny and its implications for human brain uniqueness from an evolutionary perspective. Additionally, given the recent discovery of microglia’s involvement in neurodevelopmental disorders and neurodegenerative diseases, understanding the distinct properties of human microglia could provide insights into these conditions. Source

This is a summary. Read the original at sciencedaily.com.