Furthermore, preliminary [11C]31 PET data revealed a considerable loss of PDE10A in extra-striatal brain regions, like the insular cortex and occipital fusiform gyrus, of patients with early pre-manifest HD demonstrating that dysregulation of PDE10A is an initial pathophysiological event in the progression of the disease and might be associated with cognitive and behavioral disorders in manifest HD [150]. The gene discussed is PDE10A; the disease is Huntington disease.