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bioRxiv · 10.1101/2023.12.15.571696

Population-scale skeletal muscle single-nucleus multi-omic profiling reveals extensive context specific genetic regulation

Abstract

Skeletal muscle, the largest human organ by weight, is relevant in several polygenic metabolic traits and diseases including type 2 diabetes (T2D). Identifying genetic mechanisms underlying these traits requires pinpointing cell types, regulatory elements, target genes, and causal variants. Here, we use genetic multiplexing to generate population-scale single nucleus (sn) chromatin accessibility (snATAC-seq) and transcriptome (snRNA-seq) maps across 287 frozen human skeletal muscle biopsies representing nearly half a million nuclei. We identify 13 cell types and integrate genetic variation to discover >7,000 expression quantitative trait loci (eQTL) and >100,000 chromatin accessibility QTLs (caQTL) across cell types. Learning patterns of e/caQTL sharing across cell types increased precision of effect estimates. We identify high-resolution cell-states and context-specific e/caQTL with significant genotype by context interaction. We identify nearly 2,000 eGenes colocalized with caQTL and construct causal directional maps for chromatin accessibility and gene expression. Almost 3,500 genome-wide association study (GWAS) signals across 38 relevant traits colocalize with sn-e/caQTL, most in a cell-specific manner. These signals typically colocalize with caQTL and not eQTL, highlighting the importance of population-scale chromatin profiling for GWAS functional studies. Finally, our GWAS-caQTL colocalization data reveal distinct cell-specific regulatory paradigms. Our results illuminate the genetic regulatory architecture of human skeletal muscle at high resolution epigenomic, transcriptomic, and cell-state scales and serve as a template for population-scale multi-omic mapping in complex tissues and traits.

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BibTeXRIS

Varshney, A., Manickam, N., Orchard, P., Tovar, A., Zhang, Z., Feng, F., Erdos, M. R., Narisu, N., Ventresca, C., Nishino, K., Rai, V., Stringham, H., Jackson, A. U., Tamsen, T., Gao, C., Yang, M., Koues, O. I., Welch, J. D., Burant, C. F., Williams, L. K., Jenkinson, C., DeFronzo, R. A., Norton, L., Saramies, J., Lakka, T. A., Laakso, M., Tuomilehto, J., Mohlke, K. L., Kitzman, J. O., Koistinen, H. A., Liu, J., Boehnke, M., Collins, F. S., Scott, L. J., Parker, S. C.. 2023-12-15. Population-scale skeletal muscle single-nucleus multi-omic profiling reveals extensive context specific genetic regulation. https://doi.org/10.1101/2023.12.15.571696

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