Since neuronal loss in substantia nigra is a pathological hallmark of Perry syndrome[9,10], the numbers of TH-positive midbrain DA neurons in the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) of WT Tg, G59S Tg, G71R Tg mice, and their control mice were counted using an unbiased stereological approach. The gene discussed is TH; the disease is Perry syndrome.