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bioRxiv · 10.1101/2024.03.18.585566

Unraveling a novel dual-function regulatory element showing epistatic interaction with a variant that escapes genome-wide association studies.

Abstract

Regulation of gene expression has recently been complexified by the identification of Epromoters, a subset of promoters with enhancer function. Here, we uncovered the first dual cis-regulatory element, "ESpromoter," exhibiting both enhancer and silencer function, as a regulator of the nearby genes ATP2B4 and LAX1 in single human T cells. Through integrative approach, we pinpointed functional rs11240391, a severe malaria risk variant that escapes detection in genome-wide association studies, challenging conventional strategies for identifying causal variants. CRISPR-modified cells demonstrated the regulatory effect of ESpromoter and rs11240391 on LAX1 expression and T cell activation. Furthermore, our findings revealed an epistatic interaction between ESpromoter SNPs and rs11240391, impacting severe malaria susceptibility by further reducing LAX1 expression. This groundbreaking discovery challenges the conventional enhancer-silencer dichotomy. It highlights the sophistication of transcriptional regulation and argues for an integrated approach combining genetics, epigenetics, and genomics to identify new therapeutic targets for complex diseases. HIGHLIGHTSO_LINovel dual enhancer-silencer element (ESpromoter) in a single human cell type C_LIO_LIFunctional SNP for severe malaria risk that escapes genome-wide association studies C_LIO_LIGenome editing at the SNP demonstrates a regulatory effect on LAX1 and T cell activation C_LIO_LIEpistatic interaction between SNPs increases the risk of severe malaria C_LI In briefEpistatic interaction between common variants within a novel dual enhancer-silencer regulatory element and the LAX1 promoter variant is responsible for severe malaria susceptibility through T-cell activation.

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BibTeXRIS

Adjemout, M., Nisar, S., Escandell, A., Huu, H. T. N., Torres, M., Thiam, A., Manosalva, I., Mbengue, B., Dieye, A., Spicuglia, S., Rihet, P., Marquet, S.. 2024-03-19. Unraveling a novel dual-function regulatory element showing epistatic interaction with a variant that escapes genome-wide association studies.. https://doi.org/10.1101/2024.03.18.585566

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