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Early asymmetry of gene transcription in embryonic human left and right cerebral cortex.

ABSTRACT: The human left and right cerebral hemispheres are anatomically and functionally asymmetric. To test whether human cortical asymmetry has a molecular basis, we studied gene expression levels between the left and right embryonic hemispheres using serial analysis of gene expression (SAGE). We identified and verified 27 differentially expressed genes, which suggests that human cortical asymmetry is accompanied by early, marked transcriptional asymmetries. LMO4 is consistently more highly expressed in the right perisylvian human cerebral cortex than in the left and is essential for cortical development in mice, suggesting that human left-right specialization reflects asymmetric cortical development at early stages.

SUBMITTER: Sun T

PROVIDER: S-EPMC2756725 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature

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Early asymmetry of gene transcription in embryonic human left and right cerebral cortex.

Sun Tao T Patoine Christina C Abu-Khalil Amir A Visvader Jane J Sum Eleanor E Cherry Timothy J TJ Orkin Stuart H SH Geschwind Daniel H DH Walsh Christopher A CA

Science (New York, N.Y.) 20050512 5729

The human left and right cerebral hemispheres are anatomically and functionally asymmetric. To test whether human cortical asymmetry has a molecular basis, we studied gene expression levels between the left and right embryonic hemispheres using serial analysis of gene expression (SAGE). We identified and verified 27 differentially expressed genes, which suggests that human cortical asymmetry is accompanied by early, marked transcriptional asymmetries. LMO4 is consistently more highly expressed i ...[more]

PMID: 15894532

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