Two Additional Genes Help Increase the Complexity of the Human Brain
The gene SRGAP2 is found in humans, primates and other mammals that helps control the rate of brain. Human however have two similar genes that has been found to help increase complexity of the human brain by slowing its development.
When the two additional genes were place in mice the proteins made by the human genes bound the SRGAP2 protein slowing the rate of their brains leading to the mice growing additional neuron connections. This shows that the two unique human genes have a huge affect on human brain development making them an important difference between humans and apes.