Some previous studies have found that CPn was associated with AD (Balin et al., 1998; Gerard et al., 2006; Paradowski et al., 2007), but other studies had failed to detect such an association (Taylor et al., 2002; Wozniak et al., 2003; Yamamoto et al., 2005; Hammond et al., 2010). This evidence concerns the gene CPN1 and Alzheimer disease.