APP and Alzheimer disease: The aim of the study was to characterize the influence of the expression of AβPP carrying familial AD–linked mutation (V717I) on the expression of genes coding selected synaptic proteins in the mouse brain cortex and hippocampus at the age of 3 and 12 months and to examine the impact of treatment with FTY720 (fingolimod, an S1P receptor modulator) on these changes.