A evolução acelerada dos genes do sistema nervoso na origem do Homo sapiens

sábado, maio 21, 2011

Cell, Volume 119, Issue 7, 1027-1040, 29 December 2004


Accelerated Evolution of Nervous System Genes in the Origin of Homo sapiens

Steve Dorus1, 2, 4, Eric J. Vallender1, 2, 4, Patrick D. Evans1, 2, Jeffrey R. Anderson1, Sandra L. Gilbert1, Michael Mahowald1, Gerald J. Wyckoff1, 5, Christine M. Malcom1, 3 and Bruce T. Lahn*, 1,

1 Howard Hughes Medical Institute, Department of Human Genetics, University of Chicago, Chicago, IL 60637 USA
2 Committee on Genetics, University of Chicago, Chicago, IL 60637 USA
3 Department of Anthropology, University of Chicago, Chicago, IL 60637 USA
Correspondence: Bruce T. Lahn, 773-834-4393 (phone), 773-834-8470 (fax)

4 These authors contributed equally to this work.

5 Present address: Division of Biology and Biochemistry, University of Missouri-Kansas City, Kansas City, Missouri, 64108.


Human evolution is characterized by a dramatic increase in brain size and complexity. To probe its genetic basis, we examined the evolution of genes involved in diverse aspects of nervous system biology. We found that these genes display significantly higher rates of protein evolution in primates than in rodents. Importantly, this trend is most pronounced for the subset of genes implicated in nervous system development. Moreover, within primates, the acceleration of protein evolution is most prominent in the lineage leading from ancestral primates to humans. Thus, the remarkable phenotypic evolution of the human nervous system has a salient molecular correlate, i.e., accelerated evolution of the underlying genes, particularly those linked to nervous system development. In addition to uncovering broad evolutionary trends, our study also identified many candidate genes—most of which are implicated in regulating brain size and behavior—that might have played important roles in the evolution of the human brain.