Main characteristics of BDNF gene rs6265 polymorphism genotype distributions in studies included in this meta-analysis.

*<p>The cases of these studies are late-onset Alzheimer’s disease (LOAD); Abbreviations: Na, not available; HWE, Hardy-Weinberg equilibrium. NINCDS-ADRDA, National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer’s Disease and Related Disorders Association criteria; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition); CERAD, Consortium to Establish a Registry for Alzheimer’s disease.