TPH2 and depressive symptom measurement: TPH2 rs4641528 has been reported to have high linkage disequilibrium (≥0.8) with other TPH2 SNPs related to affective disorders: rs7305115 with late‐onset depression in Brazilian (de Araujo Pereira et al., 2011) and Chinese populations (Wang et al., 2015); rs2171363 (Tsai et al., 2009) and rs10879346 (Tzvetkov, Brockmoller, Roots, & Kirchheiner, 2008) with major depression and response to antidepressant treatment; rs1352250 to hopelessness, a potential endophenotype for suicidal behavior (Lazary et al., 2012); and rs12229394 with depression accompanied by fatigue (Utge et al., 2010).