In all, sixty (n = 60) pairs were excluded: twelve (n = 12) pairs due to twin pregnancies, n = 12 due to fetal anomalies, n = 9 due to preeclampsia, and n = 26 due to maternal diseases that could affect maternal BDNF (psychiatric disorders n = 19, neurological disorders n = 7). The gene discussed is BDNF; the disease is psychiatric disorder.