RAB32 and Parkinson disease: In addition, risk genes are recognized, and in particular, carriers of GBA1 variants have increased susceptibility to developing PD.18 New monogenic causes of PD continue to be discovered, such as RAB32, which was found in several populations in Africa, North America, and Europe.19 During the course of the GP2, it is expected that a large number of variants in PD genes with potential clinical relevance will be detected in a research setting.