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Molecular insights into human brain evolution


Rapidly advancing knowledge of genome structure and sequence enables new means for the analysis of specific DNA changes associated with the differences between the human brain and that of other mammals. Recent studies implicate evolutionary changes in messenger RNA and protein expression levels, as well as DNA changes that alter amino acid sequences. We can anticipate having a systematic catalogue of DNA changes in the lineage leading to humans, but an ongoing challenge will be relating these changes to the anatomical and functional differences between our brain and that of our ancient and more recent ancestors.

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This work was supported by grants from the NINDS and Cure Autism Now. We thank M. Ruvolo and D. Reich for comments on an earlier version of this manuscript, and J. DeFilipe for the translation of the Cajal quotation. Owing to space limitations we were unable to cite directly some of the relevant work in this field. C.A.W. is an Investigator of the Howard Hughes Medical Institute.

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Correspondence to Christopher A. Walsh.

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Figure 1: Differences in cerebral cortical size are associated with differences in the cerebral cortex circuit diagram.


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