MiR-C9orf72 mice were subjected to a battery of behavioral tasks at 2, 5, 9, 12, 15, and 18 months of age in order to determine whether decreased expression of C9ORF72 caused such phenotypes, in particular anxiety-like or depression-like behaviors and alterations of social interaction, as was the case in other genetic FTD models (Yin et al., 2010; Roberson, 2012; Filiano et al., 2013). The gene discussed is C9orf72; the disease is major depressive disorder.