Figure 3: Quantile–Quantile plots of the observed P-values for association in discovery stage.
From: Two new susceptibility loci 1q24.2 and 11p11.2 confer risk to severe acne

Purple points represent the distribution of logistic regression P-values for the association of all the 809,305 SNPs in 1,031 cases and 1,031 control subjects of Chinese Han descent.