AQP4 and Alzheimer disease: Other studies have reported an association between AQP4 single nucleotide polymorphisms and the progression of cognitive decline in AD patients, of which rs9951307 and rs3875089 can lead to chronic progressive cognitive decline and rs3763040 and rs3763043 can lead to the rapid progression of cognitive decline, suggesting that the AQP4 gene product affects the cognitive decline in AD patients (Burfeind et al., 2017).