Some of the important genetic variants associated with MDD that could be affected by shiftwork are APOE, SLC6A4, ACE, GNB3, HS6ST3, HTR1A, LHFPL2, PDE11A, DISC1, MAOA, SLC6A3 (DAT1), SLC25A21, VGLL4 BDNF, P2RX7, TPH2, PDE9A
, and GRIK3 [95, 100].
To investigate the expression of phosphodiesterases in SVZ-derived neural stem cell cultures, we assessed the presence of the cGMP-specific PDE5A, PDE9A
, and PDE6C by PCR.
First, we designed real-time quantitative methylation-specific PCR (gMSP) assays (21) to target the unmethylated form of CGI084, which is linked to PDE9A (phosphodiesterase 9A), in the placenta (U-PDE9A) and the methylated form in maternal blood cells (M-PDE9A).
To test this hypothesis, we examined samples of maternal plasma obtained from 12 third-trimester pregnancies (8 male and 4 female fetuses) before and after delivery for the presence of the unmethylated form of CGI084 (U-PDE9A), which is linked to the PDE9A gene.