Results for the top 10 most significant genes from the gene-based analysis are reported in Table 3. Significant gene associations at the Bonferroni-corrected significance level were observed for neuroticism. These associated genes included C15orf17, POLR3A, MPI, SCAMP2, ULK3, COX5A. With the exception of POLR3A, they were located in a region on chromosome 15 in very tight LD, so the assignment of the same SNP to multiple genes at this locus occurred where gene boundaries overlapped. Only one of these genes showed nominal significance for the other traits: POLR3A was associated with depression symptoms (P=0.026). The most significant genes for the other traits included: PNMA1 for extraversion (P=6×10−6), GRAP for depression symptoms (P=1.9×10−5), RTTN for anxiety symptoms (P=1×10−4), and ARID3A for psychological distress symptoms (P=2.1×10−5). We checked the gene-based P-value for genes in which suggestively-associated SNPs from the GWAS were located. For extraversion, the KIAA0802 gene showed a P-value of 0.051. All the neuroticism top SNPs were in the top 10 gene list, including three genes that were genome-wide significant. For anxiety symptoms, the FHIT gene was not nominally significant (P=0.44).
