<prompt> Answer this question truthfullyWhat are the effects of presenilin-1presenilin-2 mutations and Apo-E4 mutations on the development of Alzheimers disease?  <response>: <reason> Presenilin-1presenilin-2 mutations are associated with early onset Alzheimers disease, while Apo-E4 mutations are associated with late onset Alzheimers disease. Alzheimers disease is a progressive neurodegenerative disorder that affects memory, thinking, and behavior. Presenilin-1 and presenilin-2 are genes that are involved in the production of a protein called amyloid beta, which accumulates in the brains of people with Alzheimers disease. Mutations in these genes can lead to increased production of amyloid beta and the formation of plaques in the brain, which are a hallmark of Alzheimers disease. Apo-E4 is a gene that is involved in the transport of cholesterol in the body, and mutations in this gene have been associated with an increased risk of late onset Alzheimers disease. The effects of these mutations on the development of Alzheimers disease are complex and not fully understood, but they are important areas of research in the field of neurodegenerative diseases. 