Two genes that have been associated with various psychiatric and neurological disorders and which have attracted attention due to their role in cognitive and emotional processes are the genes encoding for the enzyme catechol‐O‐methyltransferase (COMT; Dickinson & Elvevåg, 2009; Scheggia, Sannino, Luisa Scattoni, & Papaleo, 2012; Tunbridge, Harrison, & Weinberger, 2006) and the dopamine receptor D2 (DRD2; Frank & Fossella, 2011; Huertas, Bühler, Echeverry‐Alzate, Giménez, & López‐Moreno, 2012; Kellendonk et al., 2006). Here, DRD2 is linked to nervous system disorder.