The secret to happiness is one of life's biggest questions. And while circumstances do play a big role in how happy — or depressed — you are, new scientific research finds that so does DNA. A new study published in the Nature Genetics journal, says researchers discovered three genetic variants pertaining to happiness.

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Researchers analyzed the DNA of over 300,000 people from 17 different countries and found that three genetic components are linked to happiness, primarily in the central nervous system, adrenal glands (which produce hormones such as cortisol) and the pancreatic system (part of the digestion system that helps break down foods).

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This new information is exciting because it can lead to new ways to treat depression, such as better medication. So even if you aren't born with the "happiness gene," you aren't doomed to live a life of unhappiness. 

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