Recent research into the causes of mental illness suggests that genetics and environment, rather than one or the other, interact to cause psychological problems. In depression an individual's genetic make-up can predispose some people to be more susceptible to the condition when they are confronted with negative life experiences. A study of 177 male adolescents in a juvenile detention centre in Russia looked at the presence of a gene involved in the transport of the neurotransmitter dopamine (which is believed to have an important role in depression), levels of depression and the influence of rejecting child-rearing by mothers such as physical punishment, hostility, lack of respect for the child's point of view and unjustified criticism in front of others. While neither the gene or rejecting mothers on their own predicted depression the presence of both together led to a higher risk for major depression and suicidal ideation.
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