Scientists Show How a Gene Duplication Helped Our Brains Become 'Human'

            Scientists at the Scientists at the Scripps Research Institute have discovered an important mutation in the human genome, resulting in humans’ unique brain. A duplication of the SRGAP2 gene allows for more connections and a larger brain. Usually duplications in the human genome would help the original gene, which functions in neuron sprout connections. However, this mutated gene interferes with the original function. When scientists expressed the mutated gene in mice, they noticed that the major neurons of the cortex, pyramidal neurons migrated faster during maturation, but took longer to sprout the dendrites. This delayed the maturation of dendrite spines and resulted in a surprise. This delay produced many more spines when they finally matured, resulting in many more connections. The new pyramidal neuron of mice looked similar to those of humans. Scientists concluded that when the gene duplicated, many more connections between neurons would have occurred enlarging the brain. This resulted many behavioral differences between humans and primates. Scientists have added this major mutation to the evolution of humans.

            The article relates to our studies because it discusses the nervous system and specific nerve cells. We learnt about the structure and function of dendrites and the connections between the neurons. The increase of dendrites and connections would create more areas of receiving signals and transmitting them on to other neurons. The article reasons that this is what developed the uniquely large brain with millions of connections and neurons. Also, the article connects this to the evolution of humans which relates to our unit on animals and evolution.  

Scientists Show How a Gene Duplication Helped Our Brains Become 'Human'