Pelzer EA, et al. - In this investigation involving 24 parkinsonian patients and 24 healthy controls, researchers examined the interaction of degeneration in two basal ganglia (BG) pathways (the nigro-striatal and dentato-pallidal pathway) with D2 receptor signalling to illustrate an association to motor impairment and medication response. Different degeneration patterns can be found according to the ANKK1 genotype; specifically a potentially cerebellar (compensatory) role for the risk type (A1+). According to findings, differences in D2 receptor availability interact with the response to medication and nigro-striatal connectivity, but not cerebellar connectivity. This data could assist enhance each patient's individual therapy strategies and underline the need to develop therapeutics directed at axons as well as cell bodies in order to maintain their circuitry and function.