The human brain is distinguished by its remarkable size, high energy consumption and cognitive abilities, compared to all other mammals and primates. However, little is known about what has accelerated brain evolution in the human lineage. Genetic changes of brain-specific genes cannot satisfactorily explain the phenotypic adaptations in brain structure and function which occurred on the way to modern humans. Epigenetic factors may form a main source of phenotypic variation between individuals and between species. Human communication, in particular spoken language is a major cognitive ability, which has its structural basis in the enlarged human brain. In order to pinpoint human-specific epigenetic changes, we systematically compare the methylation patterns of candidate genes for human-specific communication abilities in human and non-human primate cortices.
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Schneider E, Jensen LR, Farcas R, Kondova I, Bontrop RE, Navarro B, Fuchs E, Kuss AW, Haaf T. A high density of human communication-associated genes in chromosome 7q31-q36: differential expression in human and non-human primate cortices. Cytogenet. Genome Res. 136, 97-106 (2012).
Farcas R, Schneider E, Frauenknecht K, Kondova I, Bontrop R, Bohl J, Navarro B, Metzler M, Zischler H, Zechner U, Daser A, Haaf T. Differences in DNA methylation patterns and expression of the CCRK gene in human and non-human primate cortices. Mol. Biol. Evol. 26, 1379-1389 (2009).
Schneider E, El Hajj N, Richter S, Roche-Santiago J, Nanda I, Schempp W, Riederer P, Navarro B, Bontrop RE, Kondova I, Scholz CJ, Haaf T. Widespread differences in cortex DNA methylation of the "language gene" CNTNAP2 between humans and chimpanzees. Epigenetics. 2014 Apr 1;9(4):533-45.