By Calvin J.
Postpartum depression (or PPD) is a common form of clinical depression often associated with changes in sleep or eating patterns, isolation away from friends and family, as well as difficulties with concentration and memory. According to the American Psychological Association, up to 1 in 7 women experience some form of PPD, and while it is much more common in women, research has shown that men may be similarly susceptible as well. So if PPD is so prevalent, why don’t we know more about it?
Well, a number of researchers at the University of North Carolina aim to do just that! The project currently led by Dr. Samantha Meltzer-Brody are targeting women in the US, Australia and Britain using a new iPhone app (check our their link here: http://www.pactforthecure.com). Following a brief series of questions on feelings of sadness and anxiety after childbirth, the app aims to identify women who may have suffered from PPD. The goal is to then obtain DNA samples from these individuals through a mailed out saliva donation kit (voluntarily, of course). Names and contact information would be required, however, their system ensures secure encryption of all personal data. The analytical components of the project will then be lead by Dr. Patrick F. Sullivan from the University of Carolina’s Centre for Psychiatric Genomics. They plan on genotyping over 600,000 genetic markers across the human genome to identify chromosomal regions that may exhibit a statistical difference from a control group of women who have never experienced PPD after childbirth.
Identifying genetic links to behavioural disorders are often extremely difficult and the genetics of human behaviour is really not all that well studied. While genetic links have been identified for a number of disorders including schizophrenia (meaning that risk factors leading to schizophrenia appears to be heritable), the genetics behind it has proven to be extremely complex. While a handful of mutations has been linked to schizophrenia, many more wait to be identified. And its this genetic complexity that likely drives the diversity in symptoms and severity. However, because PPD affects individuals after a unique biological experience (childbirth), Dr. Sullivan suggests that this might make it easier to study. In the New York Times (link below) he adds that some of his recent work already suggests a stronger genetic link between PPD than other types of general depression. The idea being that the number of genes involved is likely lower and the risk factor associated with each of those genes, stronger and more easily detectable.
Things to Think About?
Personally, I think this project could contribute greatly to our understanding of the genetic basis of depression. Major depression affects approximately 14.8 million people world wide (according to the Depression and Bipolar Support Alliance), and by beginning to understand the mechanisms behind PPD may allow us to set a foundation for investigating other types of depression. Although, ideas for treat or a cure will still be decades down the line.
However, this isn’t to say that the study proposed doesn’t have any potential pitfalls. The study currently aims to collect samples from 100,000 women, but will this number provide a strong statistical significance to their findings? And more importantly, how might someone’s subjectivity play into how they answer the survey questions? Like all types of depression, PPD can manifest in a large number of potential symptoms with varying severity. And unlike other illnesses, mood disorders can be difficult assess. One person’s idea of “severely depressed” or “mild problems sleeping” may be very different from someone else’s. Lastly, their app release currently targets the US, Australia and Britain only. How might this bias their results in terms of genetic background and ethnicity? In the world of genetic disorders, an individual’s genetic background can be a huge deal. Some disorders are more common in particular ethnic groups. Similarly, a particular variant or “mutation” leading to a disorder may be found in one group but not commonly in another. So why not open the program to women worldwide and have individuals list or describe their ethnic background in their response?
Anyways, the project still appears to be in its early infancy, and many of these problems (and many more that we might not even think of) may be addressed as it grows and expands. Regardless, I’m excited to see what kind of observations they make and what conclusions they might draw from it!
Do their research proposal sound interesting to you? Got anything on PPD, this project or the genetics of mood disorders that we might have missed? Share your ideas and opinions with us down below!
Kim, P. and Swain, J.E. (2007). Sad Dads: Paternal Postpartum Depression. Psychiatry. 4(2): 35–47. http ://www.ncbi.nlm.nih.gov/pmc/articles/PMC2922346/