Original ArticlesAssociation Between NOS3 Gene G894T Polymorphism and Late-onset Alzheimer Disease in a Sample From IranAzizi, Zahra PharmD*; Noroozian, Maryam MD†; Kaini-Moghaddam, Zahra BSc‡; Majlessi, Nahid PhD*Author Information *Department of Physiology and Pharmacology ‡Department of Biotechnology, Pasteur Institute of Iran †Department of Memory and Behavioral Neurology, Memory Clinic, Roozbeh Psychiatric Hospital, Tehran University of Medical Sciences, Tehran, Iran Funding: This study was funded by the Pasteur Institute of Iran. The funding source was not involved in study design; in the collection, analysis, and interpretation of data; in the writing of the report; and in the decision to submit the paper for publication. Reprints: Nahid Majlessi, PhD, Department of Physiology and Pharmacology, Pasteur Institute of Iran, Pasteur Avenue, Tehran 1316943551, Iran (e-mail: email@example.com). Received for publication December 23, 2008 accepted February 25, 2009 Competing Interests: None. Ethics Approval: The experiments were carried out in accordance with the ethical standards of the Ethics Committee of Pasteur Institute of Iran and the research protocol has been approved by that Committee. Alzheimer Disease & Associated Disorders: April-June 2010 - Volume 24 - Issue 2 - p 204-208 doi: 10.1097/WAD.0b013e3181a7c8fd Buy Metrics Abstract Alzheimer disease (AD) is the most common age-associated neurodegenerative disease caused by complicated interactions between genetic and environmental factors. The presence of the apolipoprotein ε4 allele, the only confirmed genetic risk factor for late-onset AD (LOAD), is neither sufficient nor necessary to explain all occurrences of the disease. Aberrant expression of the endothelial nitric oxide synthase (NOS3) gene has been demonstrated in degenerating neurons and glial cells in brains with AD. Molecular epidemiologic studies have presented contradictory results concerning a potential role of NOS3 gene G894T polymorphism in AD. To define a possible association of this polymorphism with LOAD in an Iranian population, we conducted a case-control study including a clinically well-defined group of 100 LOAD patients and 100 age-matched controls. G894T polymorphism in NOS3 gene was determined by polymerase chain reaction-restriction fragment length polymorphisms assay. Chi-square analysis showed a significantly increased number of individuals with the G/G genotype in AD patients compared with controls (P<0.05). These results demonstrate an association between G894T polymorphism and LOAD in an Iranian sample and the G/G genotype seems to have some effects in the development of AD either alone or through interaction with other risk factors. © 2010 Lippincott Williams & Wilkins, Inc.