Being happy can be such a chore – imagine you had to do it all the time! Apparently, Denmark has come out tops for having the happiest nation in the world following a study composed correlating happiness and their DNA.

Researchers analysed results from 13 countries, compiling data from influences like Gross Domestic Product, geography culture, religion and strength of welfare state, but it wasn’t just those things that had the biggest impact on Danish happiness.

“The results were surprising,” economist Eugenio Proto, one of the study’s authors said. “We found that the greater a nation’s genetic distance from Denmark, the lower the reported well-being of that nation.”

In other words, the more closely-related a country’s population is to Denmark, the happier that country is. The study’s second analysis found happiness levels correlate with a gene that influences serotonin, a chemical in the brain that is thought to stabilize moods. The short variant of the gene is tied to neuroticism and lower life satisfaction, and the long variant is tied to higher life satisfaction.

All we need to do is harvest their DNA and inject it into the world’s grumpy people. Mood-killers will no longer be a thing.

Check out the full story on Mashable.