Scientists Discover Obesity Gene That Helps Reduce Depression
A new study by researchers from McMaster University has revealed why some people are happier than others.
The researchers claim to have uncovered genetic evidence (the gene FTO - a major genetic contributor to obesity) which is associated with an 8 percent reduction in the risk of depression, Medical Xpress reports.
This suggests that the gene is not just an obesity gene, but a gene responsible for happiness as well.
"The difference of eight per cent is modest and it won't make a big difference in the day-to-day care of patients," 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. "But, we have discovered a novel molecular basis for depression."
Previous studies conducted on twins and siblings have revealed a 40 percent genetic component in depression. However, first author Dr. Zena Samaan, assistant professor, Department of Psychiatry and Behavioural Neurosciences said that studies attempting to associate genes with depression have been "surprisingly unsuccessful", and haven't produced any convincing evidence yet.
The latest findings are a challenge to the common perception that 'obese people get depression due to their appearance and social and economic discrimination' and that 'depressed individuals may lead less active lifestyles and change eating habits to cope with depression that causes them to become obese'.
"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," Meyre said.
For the study, researchers analyzed the genetic and psychiatric status of 17,200 participants from 21 countries. During the analysis, they found that among these patients, the previously identified obesity predisposing genetic variant in FTO was associated with an eight percent reduction in the risk of depression.
This is the first evidence that supports the FTO obesity gene to be linked to protection against major depression, and this is an important discovery, considering that one in five Canadians are affected with obesity, according to Samaan.
The research appears in a study published Nov. 20 in the journal Molecular Psychiatry.