VDR and Alzheimer disease: Older African‐Americans are two to three times more likely to develop AD than elderly whites (Alzheimer's's, 2014; Amadori et al., 2017), while the African‐Americans have higher mean VDR levels (Amadori et al., 2017; Neill et al., 2013; Richards et al., 2017) but much lower serum levels of vitamin D (Dawson‐Hughes, 2004).