Researchers know the FTO gene is a contributor to obesity. Scientists from McMaster University have uncovered something else about the so-called fat gene in a novel finding that challenges the link between obesity and depression. It seems the obesity gene is also a ‘happy gene’.
According to the Canadian investigation, there is an 8 percent lower risk of major depression associated with the FTO, obesity related gene that is carried by one-third of the population.
The FTO variant that puts people at higher risk for obesity was discovered in 2007 by British geneticists. The risk of obesity increases 30 to 70 percent, depending on whether a person carries one or two copies of the gene.
Researchers from the University of Cambridge, Oxford University and Cancer Research UK, London found the obesity related FTO gene is highly expressed in the area of the brain known as the hypothalamus that dictates how we perceive hunger and food satisfaction.
First author Dr. Zena Samaan, assistant professor at the McMaster Department of Psychiatry and Behavioural Neurosciences explained in a press release that it’s been difficult to associate genes with depression and obesity.
Senior author David Meyre, associate professor in clinical epidemiology and biostatistics at the Michael G. DeGroote School of Medicine and a Canada Research Chair in genetic epidemiology said, "We set out to follow a different path, starting from the hypothesis that both depression and obesity deal with brain activity. We hypothesized that obesity genes may be linked to depression.”
The team looked at the genetic status and mental health of patients enrolled in the EpiDREAM study led by the Population Health Research Institute. The study included 17,200 DNA samples from participants in 21 countries.
The team was able to confirm in four different studies that the FTO obesity gene is also a ‘happy gene’ and protects against major depression, regardless of body mass index. Samaan notes the importance of the finding, in light of high depression rates that affects one in five Canadians.
November 21, 2012