In our laboratory, we found that 5-HT7 receptors modulate synaptic transmission and plasticity in the hippocampus of wild-type mice and rescue defects in synaptic plasticity, learning and behavior in Fmr1 KO mice, a model of Fragile X Syndrome, and are thus a promising target for the future therapy of this disease (see below). Here, FMR1 is linked to fragile X syndrome.