It is worth noting that consistent with a recent report identifying the Cth (Cystathionine Gamma-Lyase) gene as a key HD disease effector (Paul et al., 2014), our genomic assays faithfully detected Cth as a Q111 dose-dependent down-regulated gene (Figure 7—figure supplement 1A) and Cth gene expression can be partially rescued by Sp1 overexpression (Figure 7—figure supplement 1E). The gene discussed is SP1; the disease is Huntington disease.