Figure 3.

Genetic locus of regional variation of cortical surface area (SA). (A) Manhattan plot of loci associated with PC2 of surface area. The labeled gene on chromosome 14 is DAAM1, the protein-coding gene mapped to the GWAS-significant SNPs. DAAM1 shows high levels of expression in the entire cerebral cortex during the prenatal period (see Fig. 4). (B) Regional association plot for genomic locus containing DAAM1. The horizontal axis represents the genomic position on the human chromosome 14 (hg19). The left-vertical axis indicates the –log₁₀ (P-values) obtained from the GWAS meta-analysis and the right-vertical axis, the estimated recombination rate from the HapMap samples. The red-to-blue colors indicate the degree of linkage disequilibrium (LD) between each SNP and the top SNP (rs73313052, P = 2.4E − 34). The LD was based on the pairwise squared allelic correlation r² estimated in the 1000 Genomes European reference panels (Nov 2014 EUR). The plot was created using LocusZoom (http://locuszoom.org/).