APOE and Parkinson disease: Other genes related to familial or Parkinson’s disease, parkinsonism, and Alzheimer’s disease, including SNCA, PRKN, UCHL1, PINK1, DJ-1, LRRK2, ATP13A2, GIGYF2, HTRA2, PLA2G6, FBXO7, VPS35, EIF4G1, DNAJC6, SYNJ1, DNAJC13, CHCHD2, GCH1, NR4A2, VPS13C, RAB7L1, BST1, C19orf12, RAB39B, PSEN1, GRN, APP and APOE, were screened by the targeted gene panel sequence with an Ion Torrent System (Thermo Fisher Scientific, Waltham, MA, US).