Studies have shown that double knockout (synapsin-1 and synapsin-2) mice have a lower basal blood pressure than normal mice, and additional studies from the same group showed that the same double knockout mice did not respond with progressive hypertension to treatment with cyclosporine A as is normally seen in mice, indicating that the synapsins play an integral role in control of blood pressure [46]. This evidence concerns the gene SYN1 and Hypertension.