Genetic factors are of importance for the incidence of Alzheimer's disease. Mutationshave been discovered of three genes: precursor amyloid protein, preseniline1 and preseniline 2.They may be the cause of Alzheimer's disease withthe onset under the age of 60. In the type of thedisease with alater onset (found in a vast majorityof cases), the genetic facilitating factor consists inthe presence of a polymorphic variant ofε4 apolipoproteinE. The focus of current research is onthe search for other genes increasing susceptibilityto the disease. This may not only contribute toa much better understanding of the diseasepathogenesis, but also allow implementing preventiveand therapeutic measures.