Care of expectant mothers could be revolutionised after British doctors discovered a gene which can lead to post-natal depression and an early test that can detect a woman's likelihood of suffering from the illness.
A simple blood test, which is thought would cost around £10, carried out before babies are born could identify and even prevent the condition in mothers who have the genetic variation.
A team at University Hospitals Coventry & Warwickshire NHS Trust (UHCW) and Warwick Medical School uncovered evidence of a predisposition to post-natal depression (PND) due to variants in genes of the hypothalamo-pituitary-adrenal (HPA) axis - traditionally seen as the body's "stress system".
Professor Dimitris Grammatopoulos, professor of molecular medicine and consultant in clinical biochemistry and molecular diagnostics at UHCW and Warwick Medical School, who led the research, said: "PND is a complex condition influenced by everything from a woman's financial situation to the level of support she is given. However, our research shows there is more to the 'baby blues' than environmental factors alone and has a strong genetic component. This discovery has the potential to revolutionise our care for expectant mothers by screening them before the devastating symptoms of PND set in."
His paper, which has been published by the Journal of Psychiatric Research, was based on his recent study of 200 pregnant women.
He and a team of specialists from the Departments of Obstetrics and Biochemistry identified that an overwhelming majority of women who went on to develop PND had at least one of two molecular signatures - variations in a person's DNA - which increase the risk of PND. They could be up to five times more likely to suffer from the illness.
Up to 15% of women are reported to suffer from PND, yet medics believe this figure could be much higher as many severe cases of the "baby blues" go unreported. Previous studies have identified multiple molecular signatures linked to depression. Prof Grammatopoulos tested some of these variations and has now isolated two variations specifically linked to PND, which are triggered by hormonal imbalances during pregnancy.
The team at UHCW aims to establish a three-step process for caring for pregnant women. This includes DNA screening used to determine the genetic risk of PND; a specific biomarker such as increased cortisol then used to identify changes in the HPA axis; and tools such as the 10-question Edinburgh Postnatal Depression Scale questionnaire used to correlate with symptoms of depression and genetic biomarkers.
Prof Grammatopoulos added: "At the moment, women only go to their GP once their symptoms are already severe. This new process will help identify, provide early support and, if necessary, treatment, and even prevent the illness. This innovative research can lead to development of a new patient pathway. This is a fantastic example of how personalised medicine can transform the way healthcare is delivered."
The team is now looking to demonstrate a link between the genetic variants, increased cortisol levels and PND - providing a biomarker to more accurately detect changes in HPA axis sensitivity in women with high genetic risk. Prof Grammatopoulos and his team are now carrying out the next phase of their research, recruiting approximately 1,500 women. Women can register their interest by emailing Prof Grammatopoulos and Miss Neelam Engineer at firstname.lastname@example.org. They must be pregnant with no current history of depression or other mental illness.