Regional association plot showing donor SNP associations with sST2 concentrations in plasma and serum and LD structure of the IL1RL1 region. (A) Genomic positions of SNPs are shown in mega-bases on the x-axis with mapped genes labeled by their HGNC symbols. –log₁₀P values obtained from linear regression models of donor SNPs on log-transformed sST2 concentrations in serum and plasma are shown on the left y-axis. The shape of the data point indicates the regulatory effect of the SNP; line color of the shape denotes associations from previous studies, where blue and green show genome-wide association with a trait and multiple effects (GWAS hit or association with gene expression or methylation levels), respectively. These colors indicate that a majority of the associated SNPs showed a direct regulatory effect on a transcript, indicating the denoted region contained multiple eQTL. Fill color for each SNP indicates the r² with the sentinel SNP, rs950880 (our most significant SNP-sST2 association), shown in a yellow-red gradient, with yellow indicating low LD (r² < 0.2) and red, high LD (r² > 0.8). Blue line coupled with the right y-axis shows the recombination rate in centi-Morgan (cM) per megabase. (B) Pairwise-LD heatmap of the region showing pairwise r² between SNPs. Brighter red indicates stronger correlation between SNP pairs.