FOXP2

FOXP2 is a gene which codes for a protein needed for speech and language.
It codes for "Forkhead box protein P2", which is needed for the proper development of speech and language in humans. Versions of this gene occur in many vertebrates, where it generally plays a role in communication (for instance, the development of bird song).
"FOXP2" is the first gene found which affects speech and language. The gene is more active in females than in males. In humans, mutations of "FOXP2" cause a severe speech and language disorder. 
"FOXP2" is popularly dubbed the "language gene", but this is only partly correct since there are other genes involved in language development. It directly regulates a number of other genes, including "CNTNAP2", "CTBP1", and "SRPX2".
Two amino acid substitutions distinguish the human "FOXP2" protein from that found in chimpanzees. Evidence suggests that these changes affect the functions of "FOXP2".