The gene genie

When it was announced in Nature in 2001 that the linguistic disorder displayed by members of an English family known as KE could be traced back to a mutation of a certain gene, FOXP2, Steven Pinker heralded this result as “the dawn of cognitive genetics”. While we are still a long way from being able to link cognitive mechanisms to the function of specific genes, it is certainly true that researchers, these days, are coming increasingly closer to understanding how the genome interfaces with the neural processes underlying cognitive behaviour. Among the many fundamental questions genomic studies are starting weigh in on is how brains have changed in evolutionary lineages, development, and individual differences in cognitive behaviour.

For those interested in this exiting research a number of recent overviews will be of interest. First, the great science journalist Carl Zimmer has a fantastic story in the new (November) issue of National Geographic outlining how evolution forges new complex structures. While Zimmer’s piece doesn’t focus on the evolution of the brain per se, it is a good primer on how evolution in general moves forward by “modifying old genes for new uses and even reusing the same genes in new ways” – i.e., descent with modification, as Darwin called it.

The September 29 issue of Science contained a special section of papers on how genes build the body. It contains, among other fine articles, a very nice story by Elisabeth Pennisi, “Mining the molecules that made our minds”, on current research into the genetics of human brain evolution.

In the October issue of Nature Neuroscience you can find four review papers on the role played by genes in various developmental disorders. Galaburda et al. treats developmental dyslexia, Happé, Ronald & Plomin looks at autism, and Belmonte & Bourgeron deal with Fragile X sydrome. Finally, Gary Marcus and Hugh Rabagliati argues that neither strict modularity, nor a general domain approach, is the right way to understand the relation between genes and behaviour: “On the one hand, descent with modification argues against ‘sui generis modularity,’ according to which modules are treated as independent neurocognitive entities that owe nothing to one another; on the other hand, it suggests that exclusive study of overlapping “generalist” contributions is likely to miss some of the most important evolutionary contributions. On this view, language must be understood as the joint product of domain-general ancestral inheritance and domain-specific adaptations.”

Finally, I should mention that the special issue of Cognition on “Genes, brain and cognition” – which I have mentioned earlier – has now been published (October 2006 issue). Its 7 papers will serve anybody from the cognitive sciences well who are interested in knowing more about the relation between genetics and cognition.

-Martin

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