ADRB2 and major depressive disorder: On the other hand, George et al. [35] documented interactions between genetics and psychological factor affecting pain perception, catastrophizing and depression, suggesting that polymorphisms in KCNS1 (Potassium Voltage-Gated Channel Modifier Subfamily S Member 1) and ADRB2 (Adrenoceptor Beta 2) could be useful to predict pre-operatively shoulder disability and pain duration after surgery.