According to the World Health Organization, 300 million people all over the world suffer from depression, yet it remains a mystery why it occurs. Worse, some people even think it's merely made up or that it's just sadness.

Part of why it's such an enigma is because depression varies from person to person, as is the response to treating it, but knowing the genetic makeup of the mental disease may allow us to understand it better and in turn develop better methods of combating it.

Depression, A Discussion In Genetics

A new study published in the Nature Genetics journal has identified 44 genetic variants that can increase the risk of developing major depression. Of those, 30 have never been connected to the condition previously. The researchers analyzed the genes of almost 500,000 people and claim everyone carries at least some of these variants. Their study is by far the largest academic undertaking that looks into how genetics play a role in mental health, employing 200 researchers in various parts of the world who work with the Psychiatric Genomics Consortium.

"This study is a game-changer," said Patrick F. Sullivan, co-leader of the study and director of the North Carolina School of Medicine's Center for Psychiatric Genomics. "A huge number of researchers across the world collaborated to make this paper, and we now have a deeper look than ever before into the basis of this awful and impairing human malady."

While the scientists were able to confirm 44 gene variants, they claim that thousands more are involved in depression, with each having a very modest effect on a person's risk of developing it, said senior author and King's College London professor Cathryn Lewis.

"There is certainly no single gene for depression," said Lewis.

Why This Matters

Many factors in life may contribute to one's risk of depression, but identifying the genetic factors could open new doors for further research into the biology that drives the disease. The study offers "important biological clues that we hope will lead to new and better treatments," as U.S. National Institute of Mental Health director Josh Gordon puts it. He was not involved in the research.

Depression is one of the world's most serious public health problems. Despite that, it still faces a significant level of stigma, especially in countries where professional mental health assistance isn't readily accessible. Oftentimes, depression is seen as something that can simply be erased away or buried, but this study brings us a step closer in recognizing the biological underpinnings of the disease. It could be a driving force in eliminating the stigma altogether and allow scientists to focus on developing better treatments by factoring in DNA.