Fig. 3From: An efficient genome-wide association test for multivariate phenotypes based on the Fisher combination functionThe QQ-plots of p-values for the marginal tests of association between the SNPs and each of the four addiction symptomatology variables. The x-axis is the expected −log10(p-value), and the y-axis is the observed −log10(p-value). The diagonal gray straight lines have the slope 1 and intercept 0Back to article page