In contrast, evidence of normal striatal BDNF levels at early and intermediate disease stages in these (Seo et al., 2008; Plotkin et al., 2014) and other HD mouse models (Pang et al., 2006; Potenza et al., 2007; Traficante et al., 2007; Seo et al., 2008; Cepeda et al., 2010; Bobrowska et al., 2011) argues that defects further downstream may underlie early deficiencies in neurotrophic support for MSNs in HD. This evidence concerns the gene BDNF and Huntington disease.