With the high expression of XBP1 in blood, it may increase mood disorders (OR = 1.12,95%CI, 1.07–1.18,Pfdr = 0.003),depression (OR = 1.11,95%CI, 1.05–1.17,Pfdr = 0.019) and endocarditis (OR = 1.58,95%CI, 1.29–1.94,Pfdr = 0.003) risk of develop-ment. This evidence concerns the gene XBP1 and major depressive disorder.