However, this is in contrast with some studies that report no significant change in the levels of overall GAD67 or its content within astrocytes using the APP/PS1 mouse model of AD, which differentially expresses Aβ42/Aβ40 expression (Jo et al., 2014) compared to the APPNL-F/NL-F mouse model. Here, GAD1 is linked to Alzheimer disease.