Gene expression changes during primate postnatal brain development

In development, timing is of the utmost importance, and the timing of various developmental processes are often changed during evolution. During human evolution sexual maturation has been delayed relative to other primates and this may have played a critical role for both the increase of human brain size and the rise of human-specific cognitive traits . We measured the timing of gene expression changes in the brains of humans, chimpanzees, and rhesus macaques throughout postnatal development. Human, chimpanzee and rhesus macaque post-mortem brain samples from the dorsolateral prefrontal cortex region were collected. The caudate nucleus region was additionally sampled for humans. The age ranges of the individuals in all three species covered the respective species' postnatal maturation period from infancy to young adulthood. RNA extracted from the dissected tissue was hybridized to Affymetrix® U133-plus2.0 GeneChip® arrays.