Genetic models of mice deficient in OXT or in OXT receptor (OXTR) have helped uncover the requirement of OXT signaling in myriad social behaviors including recognition of familiar and novel conspecifics (Ferguson et al., 2001, Ferguson et al., 2000Ferguson et al., 2000; Takayanagi et al., 2005; Wersinger et al., 2008), parental care (Takayanagi et al., 2005), social interactions of female with male mice during the estrous cycle (Nakajima et al., 2014), aggression (Harmon et al., 2002), and anxiety-related behaviors in male mice (Li et al., 2016). The gene discussed is OXTR; the disease is Anxiety.