A total of 1,081 adults without dementia (375 healthy subjects and 706 individuals with mild cognitive impairment) were recruited from the Alzheimer's Disease Neuroimaging Initiative (ADNI) to test the influence of BDNF Val66Met polymorphism on cognitive impairment, brain structure atrophy, and change in the levels of CSF biomarkers.
Among 200 outpatients with dementia and MCI, 146 outpatients with mild AD or A-MCI were recruited and divided into two genotypic groups, valine homozygosity (Val/Val) and methionine (Met) carriers, based on the representative BDNF functional polymorphism Val66Met.