Adjusted for age and gender, mRNA levels of KLF12 (b=−0.0122, 95% CI: −0.0244 to −0.0004), POLG (b=−0.0034, 95% CI: −0.0059 to −0.0009), OGG1 (b=−0.0012, 95% CI: −0.0018 to −0.0005) and GSK3B (b=−0.0071, 95% CI: −0.0140 to −0.0002) were downregulated in bipolar disorder patients overall, whereas PGAM1 (b=0.0070, 95% CI: 0.0009 to 0.1310) was upregulated compared with healthy control subjects (all P<0.05; Table 2). The gene discussed is POLG; the disease is bipolar disorder.