These have included homogeneous time-resolved fluorescence assays (HTRF, also termed TR-FRET) that detect soluble mutant HTT (Weiss et al., 2009), both soluble mutant and wild-type HTT (Weiss et al., 2011) and aggregated HTT (Baldo et al., 2012) in cultured cells and tissues from mouse models of Huntington’s disease. The gene discussed is HTT; the disease is Huntington disease.