Figure 1

Quantile–quantile (QQ) plot of the genome-wide association data. QQ plot of allelic χ2 test P values from autosomal SNPs following the application of all quality control filters. Good adherence of data points to the line of expectance was observed. This implies that spurious associations, characterized by an increase in the number of potential highly significant P values, had been systematically removed. All remaining slight deviations from the line of expectance in the extreme tail are presumed to reflect true-positive genetic effects.