BBC NEWS | Health | Loneliness could be in your genes:
"Loneliness may run in the family, researchers have suggested.
Teams from the Free University in Amsterdam and the University of Chicago looked at data on 8,000 identical, and non-identical, twins.
They found genetics had a significant influence on loneliness.
Loneliness has been linked to heart disease as well as emotional problems, such as anxiety, self-esteem problems and sociability.
The researchers suggest that loneliness may stem from prehistoric times, where hunter-gatherers may have deliberately shut themselves away from others so they did not have to share food.
That would have meant they were better nourished and therefore better able to survive and have children.
But they added that the strategy had a downside, in that it also developed dispositions towards anxiety, hostility, negativity and social avoidance"
