Human as well as animal research suggests that the T allele of the NPSR1 polymorphism (Pape et al., 2010; Raczka et al., 2010; Domschke et al., 2011) and the S allele of the 5HTTLPR polymorphism (Canli and Lesch, 2007; Lonsdorf et al., 2009; Klumpers et al., 2012) are vulnerability factors for enhanced anxiety levels and anxiety disorders, presumably as a result of facilitated fear conditioning (Orr et al., 2000; Mineka and Oehlberg, 2008). This evidence concerns the gene NPSR1 and anxiety disorder.