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The study involved children born using in-vitro fertilisation, comparing IVF children who were genetically related to their parents, with those who were not.
The study examined "positive and negative" parenting, finding negative parenting was linked to childhood aggression, and that depression was linked to environment, although researchers could not identify the trigger.
Prof Gordon Harold, of Dunedin, head of Otago University's centre for research on children and families, told the Otago Daily Times it was wrong to frame the study as discounting the role of genes, but rather establishing that environment was key to switching on elements of a person's genetic profile.
He said the old nature-versus-nurture debate had moved on, and it was now accepted both played a part in a person's development.
Along with researchers from Cardiff University and University College London, Prof Harold studied 1000 families with children aged 4 to 6 from the United Kingdom and the United States, for a three-year period.
Prof Harold said he had been surprised IVF children had not been used for an environmental study of its type before: previous studies involving IVF children had been concerned with how they fared compared with those naturally conceived.
By only using IVF children, it was possible to make comparisons between genes and environment that were impossible using adoptive or natural parents.
The Wellcome Trust in the United Kingdom funded the study, which has just been published in the journal Psychological Medicine.
Prof Harold said the study could provide impetus for social agencies and government policy to target specific aspects of the home environment, early in life, to promote positive outcomes for children.
"Rather than blame children's behaviour solely on the genes passed on from a biological parent to a child, look at the environments that children live in to understand better why some children develop behavioural problems while other children do not."