Bayer Andersen et al. demonstrated that GPR139 plays a neuroprotective role in an 1-methyl-4-phenylpyridinium [MPP (+)] -induced neurotoxicity model of PD, where acute slice midbrain dopaminergic neuronal cultures pretreated with a GPR139 agonist significantly withstood the apoptosis induced by 1 μM MPP (+) as the agonist dosage increased, and the coadministration of 10 μM of a GPR139 antagonist with MPP (+) significantly decreased cell viability [35]. The gene discussed is GPR139; the disease is Parkinson disease.