The Corpus Callosum
A number of genes and molecules have been identified through our research and the research of other laboratories around the world that regulate corpus callosum formation in mice. This gene list can be found here. Please send Professor Richards updates of genes if they are not on this list.
Agenesis (complete absence) or dysgenesis (malformations) of the corpus callosum is a developmental brain disorder that affects around 1:4000 people. There are around 50 different human congenital syndromes associated with agenesis or dysgenesis of the corpus callosum. A summary of these disorders can be found in ACC genetic developmental and functnl connectivity_Paul et al Nature Reviews-2007.pdf. Because agenesis or dysgenesis of the corpus callosum is associated with so many different syndromes, the symptoms of this disorder can vary widely.
At present we know a lot more about how corpus callosum formation occurs in mice than in humans. Our laboratory is dedicated to trying to translate our findings to understanding human cortical development and corpus callosum formation.
To do this we employ diffusion tensor magnetic resonance imaging to investigate cortical connectivity and brain development.
A human corpus callosum.
An MRI image of the human brain. The corpus callosum is the white horse-shoe like structure indicated by the arrow.
For more information please read our reviews of corpus callosum formation and mechanisms of axon guidance:
D. Mortimer, T. Fothergill, Z. Pujic, L.J. Richards, G.J. Goodhill (2008) Growth cone chemotaxis. Trends in Neurosciences 31: 90-98. Growth Cone and Chemotaxis _Mortimer_2007.pdf
C. Lindwall, T. Fothergilll, L.J. Richards (2007) Commissure formation in the mammalian forebrain. Current Opinion in Neurobiology 17: 3-14 Lindwall2007_Commissure formation in the mammalian - Curr Opin Neurobiol.pdf.
L.K. Paul, W.S. Brown, R. Adolphs, J.M. Tyszka, L.J.Richards, P. Mukherjee, and E.H. Sherr (2007) Agenesis of the corpus callosum: genetic, developmental and functional aspects of connectivity. Nature Reviews Neuroscience 8: 287-299. Agenesis_CC_Paul_Nat_ Rev_2007.pdf
C. Plachez, L.J. Richards (2005) Mechanisms of axon guidance in the developing nervous system. Current Topics in Developmental Biology 69: 267-346.
L.J. Richards, C. Plachez, T. Ren (2004) Mechanisms regulating the development of the corpus callosum and its agenesis in mouse and human. Clinical Genetics 66: 276-289. Mechanisms and regulation and corpus callosum and agenesis_Richards_2004.pdf
L.J. Richards (2002). Axonal pathfinding mechanisms at the cortical midline and in the development of the corpus callosum. Braz. J. Med. Biol. Res. 35: 1431-1439. Axonal pathfinding and developmnt CC_Richards_2002.pdf
National Organisation for Disorders of the Corpus Callosum
National Institute of Neurological Disorders and Stroke
(Search for Agenesis of the Corpus callosum under the alphabetical listings).
The Corpus Callosum and AgCC
Research Centres
Caltech, Corpus Callosum Research Program
http://www.emotion.caltech.edu/agcc/index.html
University of California, San Fransisco, Department of Neurology
Brain Development Research Program
http://neurology.ucsf.edu/brain/callosum/
Travis Research Institute
Links