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bioRxiv · 10.1101/638544

Large eQTL meta-analysis reveals differing patterns between cerebral cortical and cerebellar brain regions

Abstract

The availability of high-quality RNA-sequencing and genotyping data of post-mortem brain collections from consortia such as CommonMind Consortium (CMC) and the Accelerating Medicines Partnership for Alzheimers Disease (AMP-AD) Consortium enable the generation of a large-scale brain cis-eQTL meta-analysis. Here we generate cerebral cortical eQTL from 1433 samples available from four cohorts (identifying >4.1 million significant eQTL for >18,000 genes), as well as cerebellar eQTL from 261 samples (identifying 874,836 significant eQTL for >10,000 genes), and provide the results as a community resource. We find substantially improved power in the meta-analysis over individual cohort analyses, particularly in comparison to the Genotype-Tissue Expression (GTEx) Project eQTL. In addition, we observed differences in eQTL patterns between cerebral and cerebellar brain regions. We provide these brain eQTL as a common resource for use across the community in research programs. As a proof of principle for their utility, we apply a colocalization analysis to identify genes underlying the GWAS association peaks for schizophrenia and identify a potentially novel gene colocalization with lncRNA RP11-677M14.2 (posterior probability of colocalization 0.975).

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BibTeXRIS

Sieberts, S. K., Perumal, T. M., Carrasquillo, M. M., Allen, M., Reddy, J. S., Hoffman, G. E., Dang, K. K., Calley, J., Ebert, P. J., Eddy, J., Wang, X., Greenwood, A. K., Mostafavi, S., the AMP-AD Consortium,, the CommonMind Consortium (CMC),, Omberg, L., Peters, M., Logsdon, B. A., De Jager, P. L., Ertekin-Taner, N., Mangravite, L. M.. 2019-05-17. Large eQTL meta-analysis reveals differing patterns between cerebral cortical and cerebellar brain regions. https://doi.org/10.1101/638544

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