“No man is an island,” noted English poet John Donne, but now a new study of nearly a half-million people find there may be genetic roots to loneliness.

These findings also show that some genetic variations are linked to social activities like going to the pub. The results were published Tuesday in the journal Nature Communications.

Previous research has already shown that loneliness is more than just a state of mind. It’s strongly linked with an increase in all causes of death, on a l