THY1 and Alzheimer disease: On the other hand, Thy1 expression in the cortex of 5xFAD mice was substantially elevated relative to wild-type mice from 4 months of age, and at far higher levels than in the 3xTg-AD mice at 18 months of age (Figures 9H,I), again consistent with the high plaque load seen in 5xFAD mice.