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Aggression or depression 'linked to parenting at home'- 3-Dec-2010
London: Contrary to general perception that aggression or depression lies in one's genes, a new study has found that the traits may be linked to parenting at home.
An international team, led by Otago University, claims to have found that the role of positive and negative parenting practices influences a child's mental health problems, such as depression or aggression.
The study, published in the 'Psychological Medicine' journal, has suggested that the parenting environment plays a unique role in children's development.
"This finding has significant implications for all parents -- including those who are not genetically related to their children such as adoptive parents and genetically
unrelated parents of IVF 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," team leader Professor Gordon Harold said.
In fact, researchers have based their findings on an analysis of a comparison of a group of genetically related and genetically unrelated children born to parents using the in-vitro fertilisation.
The study involved the participation of 1000 families with children aged 4-6 years from the United Kingdom and the United States over a three-year period.
Mothers and fathers completed a questionnaire relating to aspects of family life including economic circumstances, family relationship experiences including parenting practices, as well as parent and child mental health symptoms.
Parent and child levels of aggression and depression were assessed among genetically related and genetically unrelated parent and child groupings.
"Associations were found between parent and child symptoms of depression and aggression among parents and children who were genetically related, but, crucially, also among parents and children who were not genetically related.
"While common genetic factors such as genes passed on from parents to their biologically related children may explain this association in the first of these groupings, they cannot explain associations in the second grouping as parents
and children are not genetically related.
"This suggests that the rearing environment children experience may explain why symptoms are passed on from one generation to the next where common genetic factors cannot account for this transmission process," Prof Harold said.
The study further examined the role of mothers and fathers respective positive (warmth) versus negative (hostile) parenting and found that parents who're hostile towards their children promoted increased levels of aggression in children, but not depression. Neither hostility nor decreased warmth explained the transmission of depressive symptoms from parent to child, suggesting that some other family environmental factors, such as distressed inter-parental relations, may be important in explaining this specific association.
