If you had behavioural problems at the age of ten you are twice as likely to be living in a stressful place at the age of 28, research at a pioneering centre at the Institute of Psychiatry in London has found.

The findings highlight some of the complex ways in which we shape our lives as a result of social, genetic and developmental factors, according to Sir Michael Rutter, director of the Social, Genetic and Developmental Psychiatry Research Centre, which was set up last year with a Pounds 2.6 million grant from the Medical Research Council. Thus the ten- year-old with disruptive behaviour becomes the 28- year-old who is unemployed or has an unstable marriage. "There is a notion that environments come randomly," says Sir Michael. "Luck comes into it but it is not just luck and all of us are in situations because of what we did or did not do."

The centre is still recruiting and has yet to find cash for a building, but many of its scientists, support staff and equipment are in place.

There are several indirect ways in which our genes can influence us. They contribute to the behaviour of our parents, who create our environment, so that an environmental effect has a partly genetic basis.

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Our genes also influence the way we behave with others, which alters how they behave towards us, so social rejection can be partly genetic. Finally, our genetic make-up partly affects our choice of whether we watch TV, read books or play football. This choice determines the environments to which we will be exposed and which will therefore influence us.

The centre is also researching developmental influences on behaviour, says Sir Michael. "Why do some people never have an attack of depression, some have one, and some have attacks throughout their lives?" In a study of step- parenting, which will be done by Judy Dunn, a developmental psychologist who has moved back from the United States, watching the complex situations develop will be crucial to dissecting influences on behaviour.

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Sir Michael says: "People have got very concerned about the supposed breakdown of the family. It is not sensible to think of step-parenting as good or bad. It has to be a concern but the evidence is that there is a complex association with risk of emotional or behavioural disturbances." The developmental approach is essential, he says. "Remarriage is happening over time and not 'an event'."

The centre's flagship study has been set up by Robert Plomin, also attracted from the US by the promise of interdisciplinarity and the assurance of an equivalent salary.

Professor Plomin is setting up a databank of all twins born in the United Kingdom between 1994 and 1996. They will be monitored for the development of mental impairment. "No one has studied mild mental impairment from a genetic point of view before," he says.

Professor Plomin's hypothesis is that language disorders and mental impairment are bound up together. He argues that a genetic propensity may nudge a child slightly in a certain direction, which causes it to create for itself a certain environment, which leads to a bigger and bigger effect. Professor Plomin has been excoriated for trying to show a genetic cause of IQ.

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The centre also needs a home. Sir Michael is waiting to hear whether Pounds 5 million can be found from a mixture of state and charity sources to renovate an accommodation block. "We're pretty optimistic," he says.