ADRB1 and frontotemporal dementia: To determine the effect of the Adrb1-A187V mutation on the accumulation of tau pathology, we crossed heterozygous Adrb1-A187V mice (Adrb1+/m) with PS19 tau mice expressing 1N4R human tau with a P301S mutation that causes a form of frontotemporal dementia (27) (Adrb1+/m;PS19).