Total number of participants (n = 414), n = 372 had AD and n = 42 asymptomatic with a history. n = 48 of the participants had PSEN1 variants, the most frequent being Glu206Ala (n = 25), Ala431Glu (n = 25) and Ile143Thr (n = 3), in addition, 21 new variants were identified. The gene discussed is PSEN1; the disease is Alzheimer disease.