Although there were no genome-wide significant results for individual SNPs, in the gene-based analysis, there was a significant hit for one locus, LOC101928162. This is long noncoding RNA site whose function remains elusive. Interestingly, among the top 30 genes were genes previously implicated in extraversion or in psychiatric disorders associated with extraversion. The low P-value for CRTAC1 (P = 2.97 x 10−5), harks back to an interesting extraversion SNP (rs7088779) in a previous GWAS on personality (Amin et al. 2013) that is located between CRTAC1 and C10orf28. RELN (P = 5.69 x 10−5) has been reported to increase the risk for schizophrenia and bipolar disorder (Kuang et al. 2011; Ovadia and Shifman 2011), while ADAM12 (7.65 x 10−5) was previously found to be involved in schizophrenia (Farkas et al. 2010), and bipolar disorder treatment (Nadri et al. 2007). The BDNF gene was also implicated in a previous extraversion GWAS (Terracciano et al. 2010), though not genome-wide significant. Liu et al. (2005) reported a trend towards association of BDNF variants with substance abuse, Jiao et al. (2011) reported an association with
