BDNF and schizophrenia: Of these BDNF gene polymorphisms, the G196A and C270T SNPs were significantly associated with this diseases in some studies (Kunugi et al., 2001; Ventriglia et al., 2002; Parsian et al., 2004; Olin et al., 2005; Nagata et al., 2011; Dai et al., 2013; Watanabe et al., 2013; Lee and Song, 2014), especially C270T polymorphism was susceptibility to East Asian schizophrenia and AD (Watanabe et al., 2013).