Jolly Old St. Nick is happy for a reason, and it may be the same reason his red coat could double as a sail.
Scientists out of McMaster University have discovered a happy gene — and it just so happens to be the same one that is a major contributor to obesity.
“So you can be obese, and happy,” said David Meyre, an associate professor at McMaster’s department of clinical epidemiology and biostatistics and a senior author of the study released Tuesday in the journal Molecular Psychiatry.
“This is the first time we know there is some biological reason, or a pathology, behind something like mental health, especially depression,” added first author Zena Samaan, an assistant professor at McMaster’s department of psychiatry and behavioural neurosciences.
The scientists set out to find out which genes leave people more susceptible to depression. What they found was that a gene that predisposes some people to obesity, called FTO, also offers some protection against depression.
Meyre, who holds the Canadian research chair in genetic epidemiology, recognized that the “unexpected” result contradicts what has long been thought to be a positive link between obesity and increased incidence of depression.
The connection between the FTO gene, obesity and lower risk of depression was found through statistical analysis of data on 27,000 people, comparing their weight, genetics and depression levels, Samaan said.
It showed that the risk of depression is reduced by 8 percent when a person carries the FTO mutation, a number both Meyre and Samaan said was considered modest.
However, Samaan added, for a disease that affects nearly one in five Canadians, understanding the role genetics plays in depression could lead to a greater understanding of its biological mechanisms and possibly even potential treatments.