Young gay men are six times more likely than those over 45 to attempt suicide.
The research has been described as a game-changer in understanding the condition.
Genes could make people more sensitive to their environment.
A major study has shown the real impact of depression on your overall physical health.
Experts say if the depression is left untreated, it can heighten the risk of another stroke.
This could be the key to getting treatment to more people in need.