Interestingly, there was little overlap between proteins dysregulated in GBA+, LRRK2+ and idiopathic subcohorts (SEMG2 and DLK1 were shared by GBA+ and the idiopathic subcohort) though in each list there is a high percentage (4/6 in GBA+, 4/7 in LRRK2+ and 10/23 in the idiopathic subcohort) of markers previously reported in relation to PD (Table 3). Here, DLK1 is linked to Parkinson disease.