We intersected R21G03-AD with DBD lines expressed under various neurotransmitter drivers to drive mutATXN3-(CAG)84, and found that combination with Gad1-DBD (P<0.05; n=12), but not with ChAT, Ple or Ddc-DBD, led to tremor (Fig. 3Ai). Here, GAD1 is linked to Tremor.