The profound and early loss of striatal type 1 cannabinoid receptors (CB1-R) in the striatum and projection area (substantia nigra reticulate and globus pallidus externus) in HD has been demonstrated by autoradiography studies on post-mortem brain samples from patients at early stages as for the A2A-R (Glass et al., 2000). The gene discussed is ADORA2A; the disease is Huntington disease.