If you just can't ever seem to get up early for that morning workout, don't be too hard on yourself. New research suggests that being an early riser is in some people's DNA -- and not in others'.
The study, which was published Tuesday in the journal Nature Communications, isolated 15 areas in the human genome that are associated with the tendency toward or against "morningness."
"In this study we set out to discover more about an individual's preference toward early rising, and were able to identify the genetic associations with ‘morningness’ as well as ties to lifestyle patterns and other traits," Dr. Youna Hu, a scientist at 23andMe and lead author of the paper, said in a statement.
In one of the largest genetic studies of its type, researchers from San Jose State University and personal genetic company 23andMe used data on more than 89,000 adults collected by 23andMe. For the first time, they drew a link between possessing certain genes and self-reports of being a "morning person."
Seven of the 15 genes linked with morningness were associated with circadian rhythms, the body's 24-hour cycle of rest and activity, which follow daily cycles of dark and light. Circadian rhythms dictate a number of physical, psychological and behavioral changes that occur throughout the day, which suggests that they also play an important role in a preference for mornings or evenings.
The results of the study also honed in on some common traits that tend to overlap with being a morning person. For instance, women and adults over the age of 60 were more likely to be morning people.
Being a morning person also seemed to come with certain health benefits. Morning people were significantly less likely to suffer from insomnia or depression than those who described themselves as night owls. They also had lower average BMIs than night owls.
"What is new is we were able to show that variation in these genes affects our individual preferences for mornings or evenings," Dr. David Hinds, a statistical geneticist at 23andMe and one of the study's authors, told The Huffington Post. "The work also implicates some genes that have not previously been known to have a circadian role, which may point to new and interesting biology."
It's important to note, however, that genetics are only one factor in being an early bird, according to the researchers.
"Our genetics influences our preferences and lifestyle choices, and with these kinds of studies becoming possible, can help us understand or explain why we have the preferences we do," Hinds said. "Still, many other factors are important, and our preferences are not predetermined by our genetics."
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