We have previously reported that GPR39 is expressed in microglia in postmortem human brain with small vessel disease (SVD) and a history of dementia, whereas in normal healthy young brain, GPR39 is predominantly expressed in pericytes (Davis et al., 2021a), suggesting that GPR39 upregulation in microglia may play a compensatory role in SVD-related dementia. Here, GPR39 is linked to dementia.