PSEN2 and Parkinson disease: Three of these variants have been described in patients with AD, PD or frontotemporal lobar degeneration and amyotrophic lateral sclerosis (Patient A:PSEN2 p.D439A;16, 17 B:CHMP2B p.I29V;18 and C:SQSTM1 p.A33V,19, 20).