Dataset Information

Allele-specific NKX2-5 binding underlies multiple genetic associations with human electrocardiographic traits

ABSTRACT: We conducted a genome-wide analysis to identify regulatory variants affecting the binding of NKX2-5, a core cardiac development transcription factor, and investigated their role in cardiac gene expression and EKG phenotypes. We generated iPSC-derived cardiomyocytes (iPSC-CMs) from a pedigree of seven whole-genome sequenced individuals, and profiled them with a variety of functional genomic assays including RNA-Seq, ATAC-Seq, and ChIP-Seq of both histone modification H3K27ac and NKX2-5. After establishing that iPSC-CMs recapitulated cardiomyocyte-specific expression and epigenetic signatures, and that genetic variants affected the variability of molecular phenotypes across the iPSC-CM lines, we identified heterozygous sites that showed allele-specific effects (ASE). We then investigated NKX2-5 ASE variants in detail by examining whether they altered cardiac TF motifs, and whether they were enriched for eQTLs and EKG GWAS-SNPs. Our data reveal that variation affecting the binding of NKX2-5 and other cardiac TFs likely serves as a molecular mechanism underlying control of numerous EKG loci across the genome, and that fine-mapping approaches, combined with molecular phenotype data from iPSC-CMs, can be used to prioritize causal variants in EKG GWAS loci.

ORGANISM(S): Homo sapiens

PROVIDER: GSE133833 | GEO | 2019/07/12

REPOSITORIES: GEO

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