Molecular evolution of the brain size regulator genes CDK5RAP2 and CENPJ
Patrick D Evans1, Eric J Vallender, Bruce T Lahn
1Howard Hughes Medical Institute, Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA.
Gene
|April 25, 2006
Summary
Genes regulating brain size, like CDK5RAP2, evolved rapidly in primates, particularly humans and chimpanzees. This suggests a role for these genes in human brain evolution.
Area of Science:
- Genetics
- Evolutionary Biology
- Neuroscience
Background:
- Primary microcephaly is a brain development disorder causing reduced brain size without other abnormalities.
- Mutations in genes like CDK5RAP2 and CENPJ are linked to primary microcephaly.
Purpose of the Study:
- To investigate the evolutionary patterns of the CDK5RAP2 gene.
- To compare the evolution of CDK5RAP2 with other primary microcephaly genes.
- To explore the role of microcephaly genes in primate brain evolution.
Main Methods:
- Comparative analysis of protein evolutionary rates.
- Examination of gene evolution across primate, rodent, and carnivore lineages.
- Focus on CDK5RAP2 and CENPJ gene evolution.
Main Results:
- CDK5RAP2 exhibits a significantly higher protein evolutionary rate in primates compared to rodents and carnivores.
- The evolutionary rate of CDK5RAP2 is particularly elevated in humans and chimpanzees.
- The evolutionary patterns of CDK5RAP2 and CENPJ align with those of microcephalin and ASPM.
Conclusions:
- The evolutionary trajectories of primary microcephaly genes suggest their involvement in primate brain evolution.
- Genes controlling brain development may have been key drivers of human brain evolution.
- Further research into these genes could illuminate the genetic basis of human brain expansion.
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