ABSTRACT
Dementia is the progressive or chronic dysfunction of cortical or subcortical functions that results in complex cognitive decline and Alzheimer's disease is the most common etiology of dementia. Currently, causal genetic mutations such as amyloid precursor protein, presenilin 1, presenilin 2 in familial Alzheimer's disease and many susceptible genes including polymorphysm of apolipoprotein E have been reported. Furthermore, genetic testings are available in person at risk for Alzheimer's disease. However, besides from results of genetic testing, there are many issues such as economics, ethics, psychological and legal. So clinician should be considered these complexities before ordering genetic test for patients with/without Alzheimer's disease.