APP and Alzheimer disease: On the genetic side of view, it has been reported that mutations in the APP gene on the chromosome 21, Presenilin1 (PSEN1) on the chromosome 14 and PSEN2 on the chromosome 1 that regulate the activity of γ secretase, and sortilin (SORT1) on the chromosome 1 that mediates surface APP transport to intracellular Golgi-ER complex are associated with AD.