If you think a new car or the perfect partner is going to make you happy, think again — new research says this is only possible with the help of your genes.

Researchers from the University of Edinburgh and the Queensland Institute of Medical Research in Brisbane have found our personalities and happiness are largely hereditary and that genetically determined personality traits affect our happiness.

The research, published in the latest issue of the journal Psychological Science, rated the personalities of 973 pairs of twins. The twins were rated using the Five Factor Model of personality, which measures neuroticism, extroversion, conscientiousness, openness and agreeableness.

The study shows identical twins have a very similar personality and well-being. But fraternal twins are only around half as similar.

This suggests that genes are responsible for certain personality traits. Those who are conscientious, extroverted and not overly neurotic are more likely to be happy. People with these personality traits also tend to have a happiness buffer to help them through hard times.

While the researchers found happiness has its roots in our genes, half is related to our work, health or relationships.

New theory of happiness?

One of the researchers, Prof. Timothy Bates, says this research is the beginning of a new theory of happiness.

"It helps us understand what was otherwise a real puzzle," he says. "Why do people tend to show stable differences in happiness? It turns out that if we want to understand happiness, we will need to understand personality…. An important implication is that personality traits of being outgoing, calm, and reliable provide a resource; we called it 'affective reserve' that drives future happiness."

'Linking happiness to personality and a focus on the positive will help our research into therapies and ways to avoid the low end of the happiness [scale] — depression.'— Prof. Timothy Bates

Prof. Robert Cummins, of the Australian Centre on Quality of Life at Deakin University in Melbourne, says it's in our best interests to be positive, and personality has a 'set point' around which we maintain our well-being.

"The average person feels well-satisfied with themselves and their life, and that's the average set point … even people with low set points feel positive," he says.

"Remaining positive in your outlook is incredibly important, it gives you a motivation for doing something when you wake up in the morning and makes you get on with life and do things."

Bates says the latest research confirms most us are happy for much of the time, that we generally like who we are and we don't want to change too much. But he says the study could shed some light on mood disorders such as depression.

"Linking happiness to personality and a focus on the positive will help our research into therapies and ways to avoid the low end of the happiness [scale] — depression."