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. This evidence concerns the gene HTT and juvenile Huntington disease.