Human brain development: Gene for size found (Introduction)

by David Turell , Friday, February 27, 2015, 15:27 (3557 days ago) @ David Turell

A gene found in H. sapiens, Neanderthals and Denisovans, but not in chimps drives stem cell production and causes the size we have.:-http://medicalxpress.com/news/2015-02-gene-brain-size-humans.html-"During evolution our genome must have changed in order to trigger such brain growth. Wieland Huttner, Director and Research Group Leader a the Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), and his team identified for the first time a gene that is only present in humans and contributes to the reproduction of basal brain stem cells, triggering a folding of the neocortex. The researchers isolated different subpopulations of human brain stem cells and precisely identified, which genes are active in which cell type. In doing so, they noticed the gene ARHGAP11B: it is only found in humans and in our closest relatives, the Neanderthals and Denisova-Humans, but not in chimpanzees. This gene manages to trigger brain stem cells to form a bigger pool of stem cells. In that way, during brain development more neurons can arise and the cerebrum can expand. The cerebrum is responsible for cognitive functions like speaking and thinking. "