Some people, it seems, find it very easy to smile. A little joke or a kind word can cause them to beam while a funny cat video can make them ROFL IRL. They might also have the opposite reaction more often, too: quicker to tear up and weep for their loss or someone else’s. On the other hand, some of us may be more stoic and stern, less likely to show emotion.

The secret, according to researchers at Northwestern University, is in your DNA.

The Long and Short of It

The gene in question is 5-HTTLPR, which, unfortunately, doesn’t have a more common name or nickname. The known function of this gene is regulation of serotonin levels, and it has two different variations, a long and short version. As with all genes, we inherit one version from each parent, so some people might have two long versions, some people two short, and some people one of each.

In order to test the effect of this variation, researchers designed a series of tests that they used to determine the marginal emotional response of 336 subjects. First, subjects were shown cartoons that were just a little funny, including “The Far Side,” and several from The New Yorker. Second, subjects were shown a short humorous clip from the movie Strangers in Paradise. Finally, subjects were asked to talk with their spouse about a previous or ongoing disagreement.

Responses were recorded during the experiment, and rated using the Facial Action Coding System (FACS). FACS is a system that looks at subtle movements in the face to determine what emotion a person is showing and to what extent. It’s a truly fascinating tool.

Having identified which people responded to the stimuli, researchers tested them for variations of 5-HTTLPR

People who had the short version of 5-HTTLPR were more likely to respond to the stimuli.

Genetics Is neither Destiny nor Dentistry

Researchers in this study reminded us, “The fundamental truth of genes is that they don’t have the final say.” Although people with the short version of 5-HTTLPR are more likely to respond emotionally, especially to smile, there are a number of factors that will influence how easy it is for you to smile.

For example, if you smile, and people tend to smile back, you’re going to be more likely to keep smiling. If, on the other hand, people react with a neutral expression, or, worse, a disgusted expression, you might stop smiling so often. Your ability to smile easily might also be influenced by your own sense of your smile. If you don’t have confidence in the appearance of your smile, you might be reluctant to smile.

In both cases, your ability to smile easily can be influenced by the appearance of your smile. If you are finding it hard to smile, either because of the reaction of others or because of your own sense of your smile, cosmetic dentistry might help.

To learn whether cosmetic dentistry is right for you, please call  for an appointment with a Mohegan Lake cosmetic dentist at Advanced Dentistry of Mohegan Lake.