Edinburgh: Happiness is in your genes, according to the latest research from the University of Edinburgh.

Fifty per cent of our disposition is genetic, with external factors such as money, career, health, relationships accounting for the rest, says the report in the journal Psychological Science.

Those who are lucky enough to inherit a happy disposition also have extra reserves for times of stress, the researchers who studied 900 sets of twins found.

Leader researcher Dr Alexander Weiss says: “Together with life and liberty, the pursuit of happiness is a core human desire. Although happiness is subject to a wide range of external influences we have found that there is a heritable component of happiness which can be entirely explained by genetic architecture of personality.”

Those who have inherited a poor set of genes have to work harder at being happy, they said.