Additional file 2: of A randomized controlled trial of folic acid intervention in pregnancy highlights a putative methylation-regulated control element at ZFP57

Figure S2. QQ plot shows no evidence of population substructure effects. The observed Chi-squared (χ2) values (open circles), plotted as –log10 of the p value for both sample groups, fit tightly to the expected χ2 values (red line), indicating little evidence of association due to population substructure effects and that the top hits which deviate from the line (right-hand side) are likely to represent true differences due to loci with large effects. (PDF 332 kb)