All too often, we find ourselves feeling pity toward clinically obese individuals, trying to navigate their way about normal life. Take the London Underground as an example, where those fixed armrests limit seat width to about 70 cm, forcing anyone wider to either stand up or quite literally spill over the edges – not so dignified. It’s a depressing sight, and for years now the assumption that these obese individuals are indeed depressed has been commonplace.
Last month, however, came a challenge to this notion when scientists from McMaster University published a paper in the journal of Molecular Psychiatry providing evidence to suggest the gene FTO, the major genetic contributor to obesity, is simultaneously linked to an eight per cent reduction in the risk of depression. David Meyre, the senior author of this paper, set about his research with an open mind hypothesizing that “obesity genes may be linked to depression”, but putting no other expectations upon the results of his studies.
This result has convincing support from four different depression studies: The McMaster researchers used 17,200 DNA samples in patients from over twenty different countries, all enrolled in the EpiDREAM study led by the Population Health Research Institute. Subsequently, this finding was confirmed in three other large international genetic studies.
Although this eight per cent reduction in depression is no groundbreaker when it comes to treatment of patients today, it contributes to lifting the haze that surrounds the genetic basis of depression. Up until now, although twin studies have shown a forty per cent genetic component in depression, the molecular basis that underlies this disorder has slipped through the fingers of researchers. Therefore, this discovery represents a step closer in the direction of more completely understanding where depression comes from and how in future we might develop new treatments to tackle it.
Written by Ruth Waxman.