Growing up without a father can permanently alter the BRAIN: Fatherless children are more likely to grow up angry and turn to drugs Canadian scientists believe growing up in a fatherless household could have a greater impact on daughters than on sons They said growing up without a father could permanently alter the structure of the brain and produce children who are more aggressive Dr Gabriella Gobbi of McGill University in Canada said that the main impacts were seen in the prefrontal cortex Growing up without a father could permanently alter the structure of the brain and produce children who are more aggressive and angry, scientists have warned. Children brought up only by a single mother have a higher risk of developing "deviant behaviour," including drug abuse, new research suggests. It is also feared that growing up in a fatherless household could have a greater impact on daughters than on sons. More than one million children in the UK currently have no contact with their father while they are growing up, a figure that is growing by 20,000 a year More than 1million children in the UK currently have no contact with their father while they are growing up, a figure that is growing by 20,000 a year. Dr Gabriella Gobbi, who carried out the research with colleagues at the medical faculty at McGill University in Canada, said: "This is the first time research findings have shown that paternal deprivation during development affects the neurobiology of the offspring." The research, which was carried out on mice, compared the social behaviour and brain anatomy of youngsters with two parents to those growing up with mothers alone. The team said the findings had direct relevance to human society. They used California mice, which, like humans, are monogamous and raise their offspring together. Francis Bambico, of the Centre for Addiction and Mental Health in Toronto, who also worked on the project, said: "Because we can control their environment, we can equalise factors that differ between them. Children brought up only by a single mother have a higher risk of developing 'deviant behaviour', including drug abuse (pictured) new research suggests. Previous studies have said girls in particular have been shown to be at risk for substance abuse Mice studies in the laboratory may therefore be clearer to interpret than human ones, where it is impossible to control all the influences during development. The brains of the fatherless mice developed differently, Dr Gobbi said, with the main impacts seen in the prefrontal cortex - the part of the brain which controls social and cognitive activity. The study, published in the journal Cerebral Cortex, found that those mice raised without a father displayed signs of "abnormal social interactions" and were far more aggressive than mice raised with both parents. The difference was far more pronounced in daughters than in sons and females raised without fathers also had a greater sensitivity to the stimulant drug amphetamine. Growing up without a father could permanently alter the structure of the brain and produce children who are more aggressive and angry, scientists said Dr Gobbi said: "The behavioural deficits we observed are consistent with human studies of children raised without a father. These children have been shown to have an increased risk for deviant behaviour and in particular, girls have been shown to be at risk for substance abuse. This suggests that these mice are a good model for understanding how these effects arise in humans. The report said the behaviour of the mice was "consistent with studies in children raised without a father, highlighting an increased risk for deviant behaviour and criminal activity, substance abuse, impoverished educational performance and mental illness." It added: "Our results emphasise the importance of the father during critical neurodevelopmental periods, and that father absence induces impairments in social behaviour that persist to adulthood." Dr Gobbi said the results suggested both parents are vital for children's mental health development and hoped the findings would spur researchers to look more deeply into the role of fathers. A separate report by the Centre for Social Justice, published in June this year, found that more than 1million British children currently live without a father and have no adult male role model, a figure that is rising by 20,000 a year. Some of the poorest parts of the country are becoming "men deserts," the report found, because there are so few visible male role models for children. In the Manor Castle ward of Sheffield 75 per cent of households are headed by a single parent, most commonly a woman.