New research, 'Blood mononuclear cell gene expression signature of postpartum depression,' is the subject of a report. "In sorrow thou shalt bring forth children (Genesis 3:16) seems as relevant today, with one of seven mothers afflicted by a depressive episode, constituting the most common medical complication after delivery. Why mothers are variably affected by mood symptoms postpartum remains unclear, and the pathogenesis and early molecular indicators of this divergent outcome have not been described," scientists in Jerusalem, Israel report (see also Postpartum Depression Genetics).

"We applied a case-control design comparing differential global gene expression profiles in blood mononuclear cells sampled shortly after delivery at the time of inception of postpartum depression (PD). Nine antidepressant naive mothers showing high depressive scores and developing a persisting major depressive episode with postpartum onset were compared with 10 mothers showing low depressive scores and no depressive symptoms on prospective follow-up. A distinctive gene expression signature was observed after delivery among mothers with an emergent PD, with a significant overabundance of transcripts showing a high-fold differential expression between groups, and correlating with depressive symptom severity among all mothers. Early expression signatures correctly classified the majority of PD patients and controls. Those developing persisting PD exhibit a relative downregulation of transcription after delivery, with differential immune activation, and decreased transcriptional engagement in cell proliferation, and DNA replication and repair processes. Our data provide initial evidence indicating that blood cells sampled shortly after delivery may harbor valuable prognostic information for identifying the onset of persisting PD," wrote R.H. Segman and colleagues, Hadassah University, Department of Psychiatry.

The researchers concluded: "Some of the informative transcripts and pathways may be implicated in the differential vulnerability that underlies depression pathogenesis."

Segman and colleagues published their study in Molecular Psychiatry (Blood mononuclear cell gene expression signature of postpartum depression. Molecular Psychiatry, 2010;15(1):93-100, 2).

For more information, contact R.H. Segman, Hadassah-Hebrew University Medical Center, Dept. of Psychiatry, Jerusalem, Israel.

Publisher contact information for the journal Molecular Psychiatry is: Nature Publishing Group, 345 Park Avenue South, New York, NY 10010-1707, USA.