Huntington’s Disease is an autosomal dominantly inherited neurodegenerative disease, in which an expansion of the cytosine–adenine–guanine (CAG) repeat in the gene encoding for the N-terminal region of the huntingtin protein (htt) leads to the formation of a polyglutamine stretch (mhtt; Bano et al., 2011). The gene discussed is HTT; the disease is juvenile Huntington disease.