(C) Properties of eQTLs at increasing significance levels. As the threshold for significant linkage increases (p-value decreases, or LOD score increases), the proportion of cis-eQTLs (black) increases. The fraction of all eQTLs with sex effects (red) and cis-eQTLs with sex effects (blue) remains relatively constant at increasing thresholds. The dashed line indicates the genome-wide significance threshold (p < 5 × 10−5; genome-wide p < 0.05).