CTSH and Parkinson disease: Also, 59 unique proteins were associated with AD, and 10 of them (17%) showed an association with AD and an additional neurological disease (CTF1, NSF and PRSS53 with PD; SIGLEC9 with ALS; CR1, CTSH, PARP1 and PVR with MS; LRRC37A2 with both PD and ALS; and IDUA with PD, ALS and MS).