Differential gene expression in patients versus controls validated by qPCR in the discovery set.

<p>The X-axis depicts the relative fold changes in gene expression in the patients compared to controls. For each gene the first (pale grey) bar depicts the fold change in microarray expression levels, the second (mid grey) bar shows the change in microarray intensities and the final (black) bar shows the qPCR 2exp ΔΔCT change. Values are given as mean + SD. A relative fold change of ≤1 or −1 indicates no effect.</p

Differential gene expression in patients versus controls determined qPCR in the replication set.

<p>The X-axis depicts the relative fold changes in gene expression in the patients compared to controls. depicted as the qPCR 2exp ΔΔCT change. Values are given as mean + SD. A relative fold change of ≤1 or −1 indicates no effect.</p

Differential gene expression in controls due to medication.

<p>The x-axis the average change in expression following the use of statins and aspirin depicted as 2expΔΔCT. Values are given as mean + SD. A relative fold change of ≤1 or −1 indicates no effect. For ADRB2 and ABCG1 the changes were significant; p = 0.04 and p<0.001 respectively.</p

Baseline characteristics Patients and Controls.

<p>Baseline characteristics Patients and Controls.</p

Large-Scale Gene-Centric Analysis Identifies Novel Variants for Coronary Artery Disease

Coronary artery disease (CAD) has a significant genetic contribution that is incompletely characterized. To complement genome-wide association (GWA) studies, we conducted a large and systematic candidate gene study of CAD susceptibility, including analysis of many uncommon and functional variants. We examined 49,094 genetic variants in ~2,100 genes of cardiovascular relevance, using a customised gene array in 15,596 CAD cases and 34,992 controls (11,202 cases and 30,733 controls of European descent; 4,394 cases and 4,259 controls of South Asian origin). We attempted to replicate putative novel associations in an additional 17,121 CAD cases and 40,473 controls. Potential mechanisms through which the novel variants could affect CAD risk were explored through association tests with vascular risk factors and gene expression. We confirmed associations of several previously known CAD susceptibility loci (eg, 9p21.3:p<10−33; LPA:p<10−19; 1p13.3:p<10−17) as well as three recently discovered loci (COL4A1/COL4A2, ZC3HC1, CYP17A1:p<5×10−7). However, we found essentially null results for most previously suggested CAD candidate genes. In our replication study of 24 promising common variants, we identified novel associations of variants in or near LIPA, IL5, TRIB1, and ABCG5/ABCG8, with per-allele odds ratios for CAD risk with each of the novel variants ranging from 1.06–1.09. Associations with variants at LIPA, TRIB1, and ABCG5/ABCG8 were supported by gene expression data or effects on lipid levels. Apart from the previously reported variants in LPA, none of the other ~4,500 low frequency and functional variants showed a strong effect. Associations in South Asians did not differ appreciably from those in Europeans, except for 9p21.3 (per-allele odds ratio: 1.14 versus 1.27 respectively; P for heterogeneity = 0.003). This large-scale gene-centric analysis has identified several novel genes for CAD that relate to diverse biochemical and cellular functions and clarified the literature with regard to many previously suggested genes

Overview of design and findings.

<p>Among the 7 identified loci, we defined those close to (<1 cM) published hits <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003500#pgen.1003500-LangoAllen1" target="_blank">[25]</a>, <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003500#pgen.1003500-Speliotes1" target="_blank">[29]</a>, <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003500#pgen.1003500-Heid1" target="_blank">[31]</a> as <i>near published hit</i>s and <i>novel</i> otherwise. Novel loci with sex-combined discovery P-value<5.8×10⁻⁵, which is the P-value cut-off corresponding to 5% FDR, were declared as loci that <i>could have been discovered also with sex-combined analysis</i>, and otherwise that these <i>would have been missed without the sex-stratified analyses</i>. FDR = false discovery rate.</p

Seven identified SNPs compared to previously published loci.

a<p>The Effect allele refers to a positive effect direction in the discovery stage for the trait and gender, the SNP was selected for;</p>b<p>Gene near this SNP which was published previously from sex-combined analyses.</p><p>The seven SNPs with sex difference are considered to depict a known locus, if the index SNP is close to a published top SNP (<1 cM). These include four of the previously reported sexually dimorphic WHR loci (Heid et al., Nat Genet 2010).</p

Consistently higher effect sizes for women for all seven loci.

<p>Shown are beta-estimates and 95% confidence intervals for the seven identified SNPs (also stating the phenotype for which the SNP was selected for).</p

Seven SNPs show sex difference.

a<p>Trait and sex for which the SNP was selected;</p>b<p>Gene labels state the nearest gene or the gene as published previously; details on all genes near the association signal can be found in the <a href="http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1003500#pgen.1003500.s002" target="_blank">Figure S2</a>;</p>c<p>One-sided P-Values.</p>d<p>larger sample size due to one additional study that did not have hip circumference, and therefore could not contribute to WHRadjBMI.</p>e<p>smaller sample size as this SNP was not on Metabochip.</p><p>Shown are the seven SNPs with significant (at 5% false discovery rate) sex difference in the follow-up data. These seven SNPs exhibit genome-wide significant association in women (joint discovery and follow-up <i>P_women</i><5×10−8) and only two of these show nominally significant association in men (joint <i>P_men</i><0.05). The three loci MAP3K1, HSD17B4, and PPARG are shown here for the first time for their anthropometric trait association as well as for sex-difference.</p

Genome-wide scan for sex-specific genome-wide association highlights numerous loci.

<p>(a) Manhattan plot showing the men-specific (upward, up to 60,586 men) and women-specific (downward, up to 73,137 women) association P-values from the discovery with the 619 selected loci colored by the phenotype for which the locus was selected; (b) QQ-plot showing the sex-specific association P-values as observed against those expected under the null overall phenotypes (black) and for each phenotypes separately (colored).</p