Are you lonesome tonight? According to a new human genetics study, your genes could be to blame.
Researchers at the University of California San Diego School of Medicine looked at the genetics of 10,760 people aged over 50 years old to see if there was any link to how lonely they felt over their lifetime, rather than just occasionally due to circumstance.
Although the study suggested that environmental factors play a larger role in long-term feelings of loneliness, the researchers described the loneliness trait as heritable and accountable for up to 27 percent of an individual's feelings of social isolation. In their paper, published in Neuropsychopharmacology, they explain how some people are genetically programmed to feel loneliness more strongly than others.
Loneliness is a very subjective thing. But, as lead author and professor of psychiatry Abraham Palmer explains, our genetics can determine how strongly we feel it.
“For two people with the same number of close friends and family, one might see their social structure as adequate while the other doesn’t,” Palmer said in a statement. “And that’s what we mean by ‘genetic predisposition to loneliness’ — we want to know why, genetically speaking, one person is more likely than another to feel lonely, even in the same situation.”
Palmer and his team studied the genetic information of 10,760 people that had been collected by a survey on genetic and health information by the Health and Retirement Study. The survey asked the participants three well-established questions that measure loneliness without actually mentioning the word "lonely", which many people are more reluctant to admit to. The questions were: "How often do you feel that you lack companionship?", "How often do you feel left out?" and, "How often do you feel isolated from others?"
They also accounted for gender, age, and marital status – as all these factors play a key role in how lonely people can become.
By pairing the genetic information and the results of the questionnaire, they found that a lifelong tendency to feel lonely is a “modestly heritable” trait and "identified strong genetic correlations between loneliness, neuroticism and a scale of ‘depressive symptoms’".
They estimated that a genetic predisposition can account for 14 to 27 percent of an individual's tendency to feel lonely.
The next step for the researchers is to identify the specific genetic variations and the molecular mechanisms that influence loneliness. While the news might not seem optimistic for people suffering from chronic loneliness, hopefully this will help to identify and treat psychiatric disorders associated with feelings of social isolation.
