Transcriptomic insights into human brain evolution: acceleration, neutrality, heterochrony

Somel, Mehmet
Liu, Xiling
Primate brain transcriptome comparisons within the last 12 years have yielded interesting but contradictory observations on how the transcriptome evolves, and its adaptive role in human cognitive evolution. Since the human-chimpanzee common ancestor, the human prefrontal cortex transcriptome seems to have evolved more than that of the chimpanzee. But at the same time, most expression differences among species, especially those observed in adults, appear as consequences of neutral evolution at cis-regulatory sites. Adaptive expression changes in the human brain may be rare events involving timing shifts, or heterochrony, in specific neurodevelopmental processes. Disentangling adaptive and neutral expression changes, and associating these with human-specific features of the brain require improved methods, comparisons across more species, and further work on comparative development.


Evolution of Primate Gene Expression: Drift and Corrective Sweeps?
Chaix, R.; Somel, Mehmet; Kreil, D. P.; Khaitovich, P.; Lunter, G. A. (Genetics Society of America, 2008-11-01)
Changes in gene expression play an important: role in species' evolution. Earlier studies uncovered evidence that the effect of mutations on expression levels within the primate order is skewed, with many small downregulations balanced by fewer but larger upregulations. In addition, brain-expressed genes appeared to show an increased rate of evolution on the branch leading to human. However, the lack of a mathematical model adequately describing the evolution of gene expression precluded the rigorous establ...
Evolution of Neuronal and Endothelial Transcriptomes in Primates
Giger, Thomas; Khaitovich, Philipp; Somel, Mehmet; Lorenc, Anna; Lizano, Esther; Harris, Laura W.; Ryan, Margaret M.; Lan, Martin; Wayland, Matthew T.; Bahn, Sabine; Paeaebo, Svante (Oxford University Press (OUP), 2010-01-01)
The study of gene expression evolution in vertebrates has hitherto focused on the analysis of transcriptomes in tissues of different species. However, because a tissue is made up of different cell types, and cell types differ with respect to their transcriptomes, the analysis of tissues offers a composite picture of transcriptome evolution. The isolation of individual cells from tissue sections opens up the opportunity to study gene expression evolution at the cell type level. We have stained neurons and en...
Metabolic changes in schizophrenia and human brain evolution
Khaitovich, Philipp; Lockstone, Helen E.; Wayland, Matthew T.; Tsang, Tsz M.; Jayatilaka, Samantha D.; Guo, Arfu J.; Zhou, Jie; Somel, Mehmet; Harris, Laura W.; Holmes, Elaine; Paeaebo, Svante; Bahn, Sabine (2008-01-01)
Background: Despite decades of research, the molecular changes responsible for the evolution of human cognitive abilities remain unknown. Comparative evolutionary studies provide detailed information about DNA sequence and mRNA expression differences between humans and other primates but, in the absence of other information, it has proved very difficult to identify molecular pathways relevant to human cognition.
USP32 is an active, membrane-bound ubiquitin protease overexpressed in breast cancers
AKHAVANTABASI, Shiva; AKMAN, Hesna B.; SAPMAZ, Aysegul; Keller, Jennifer; Petty, Elizabeth M.; Erson Bensan, Ayşe Elif (Springer Science and Business Media LLC, 2010-08-01)
USP32, on chromosomal band 17q23.1-17q23.2, is a highly conserved but uncharacterized gene that gave rise during evolution to a well-known hominoid-specific proto-oncogene, USP6. We investigated the expression profile of USP32 in human tissues and examined its functions to gain insight into this novel member of the well-conserved ubiquitination system. We detected ubiquitous USP32 expression across tissues and confirmed the predicted deubiquitination function owing to the presence of conserved peptidase sig...
Functional characterization of microrna-125b expression in MCF7 breast cancer cell line
Tuna, Serkan; Erson Bensan, Ayşe Elif; Department of Biology (2010)
microRNA dependent gene expression regulation has roles in diverse processes such as differentiation, proliferation and apoptosis. Therefore, deregulated miRNA expression has functional importance for various diseases, including cancer. miR-125b is among the commonly downregulated miRNAs in breast cancer cells . Therefore we aimed to characterize the effects of miR-125b expression in MCF7 breast cancer cell line (BCCL) to better understand its roles in tumorigenesis. Here, we investigated mir-125 family mem...
Citation Formats
M. Somel and X. Liu, “Transcriptomic insights into human brain evolution: acceleration, neutrality, heterochrony,” CURRENT OPINION IN GENETICS & DEVELOPMENT, pp. 110–119, 2014, Accessed: 00, 2020. [Online]. Available: