Why are some people happier than others? The gene FTO, which is a significant gene associated with obesity, is also linked to an 8% decrease in a person's chances of developing depression, according to researchers from McMaster University in their recent study published in Molecular Psychiatry.

The experts state that FTO is not only a gene associated with obesity, but also happiness.

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 and Dr. Zena Samaan, assistant professor, Department of Psychiatry and Behavioral Neurosciences, as well as individuals from the Populations Heath Research Institute of McMaster University and Hamilton Heath Sciences carried out the study.

Meyre commented:

"The difference of eight per cent is modest and it won't make a big difference in the day-to-day care of patients. But, we have discovered a novel molecular basis for depression."

The report states that previous trials involving twins and brothers and sisters revealed a 40% genetic element of depression, but studies that have tried to find an association between genes and depression have, according to Samaan, been "surprisingly unsuccessful" and have not found any evidence suggesting a link.

Researchers from the new trial are disagreeing with the usual impressions that are associated with the link between obesity and depression. Often times it is believed that when people are obese, they develop depression because they are unhappy with the way they look.

On the other hand, many people believe that depressed individuals often end up obese because they do not lead active lives, or eat differently because of the depression, therefore leading to weight gain. A 2010 study directly linked obesity and depression to one another..

Meyre continued, "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."

Experts analyzed the genetic and psychiatric states of participants involved in the EpiDREAM study, which examined 17,200 DNA samples taken from individuals across 21 different countries.

The scientists discovered that the priorly established genetic alteration in FTO that also makes them vulnerable, is linked to a decrease of 8% in chances of depression development. The experts validated their discoveries by looking at the genetic statuses of participants involved in 3 large worldwide studies.

Meyre noted that because the same link was discovered in 4 separate studies, their findings are concrete. Their study was the "first evidence" to explain the link between the FTO obesity gene and a defense against severe depression, separate from its impact on body mass index.

Samaan said, "This is an important discovery as depression is a common disease that affects up to one in five Canadians."

Written by Christine Kearney