Maternal antenatal depression and offspring DNA methylation

Objective Research on the link between antenatal depression and alterations in offspring DNA methylation is sparse and inconsistent. This study aimed to provide a robust and rigorous test of the association between maternal antenatal depression and offspring DNA methylation in neonatal and middle childhood (8–10 years) periods. Methods Moderate to severe maternal antenatal depression was identified via a combination of diagnosis codes from outpatient and inpatient encounters during pregnancy and self-reported symptom severity on birth certificates. Offspring DNA methylation was quantified from dried blood spot and venous blood samples in the neonatal and middle childhood periods, respectively. Results Of 733 mothers with available data in the neonatal period, 53 (7%) experienced moderate to severe antenatal depression. In middle childhood, 15 (9%) of the 161 mothers with available data experienced moderate to severe antenatal depression. In the neonatal period, no probes passed false discovery rate (FDR) correction. In middle childhood, antenatal depression was associated with hypomethylation at two probes after adjustment and FDR correction: cg06112204 (in MAD1L1; β = −1.68, SE = 0.29) and cg17830140 (in POLRMT , β = −1.94, SE = 0.36). Both probes had a similar direction and magnitude when controlling for postnatal depression (β = −1.71, SE = 0.34 and β = −1.78, SE = 0.42, respectively). cg06112204 was also hypomethylated in the neonatal sample (β = −0.49, SE = 0.21), but cg17830140 was not (β = 0.07, SE = 0.22). Conclusions Methylation of other probes in the MAD1L1 gene have previously been associated with depression phenotypes in adolescents and adults, lending credibility to the finding that antenatal depression is associated with hypomethylation of cg06112204 in offspring.