Derived from data made available by the Genotype Tissue Expression (GTEx) project (Lonsdale et al. 2013), which provides \(z\)-scores for assessing the significance of effects of genetic variants (single nucleotide polymorphisms, or SNPs) on gene expression across 44 human tissues. To reduce the data to a more manageable size, Urbut et al. (2019) chose the "top" SNP for each gene --- that is, the SNP associated with the largest (absolute) \(z\)-score over all 44 tissues. This yields a \(16,069 \times 44\) matrix of \(z\)-scores, with rows corresponding to SNP-gene pairs and columns corresponding to tissues. The dataset included here is further subsampled down to 1000 rows.
gtex is a matrix with 1000 rows and 44 columns, with rows
corresponding to SNP-gene pairs and columns corresponding to tissues.
Lonsdale et al. (2013). "The Genotype-Tissue Expression (GTEx) project." Nature Genetics 45(6), 580--585.
Urbut, Wang, Carbonetto, and Stephens (2019). "Flexible statistical methods for estimating and testing effects in genomic studies with multiple conditions." Nature Genetics 51(1), 187--195.