ACE and major depressive disorder: In line with these findings, a recent study involving 40,675 patients with schizophrenia and 64,643 controls, 20,352 patients with BD and 31,358 controls, and 135,458 patients with MDD and 344,901 controls revealed that a 1-SD lower blood expression of the ACE gene was associated with a lower systolic blood pressure of 4.0 (95% CI,2.7-5.3) mm Hg, but increased risk of schizophrenia (odds ratio (OR), 1.75; 95% CI) [113].