Many mental-health problems have a strong hereditary element and bipolar disorder is one of them. A study of 1,015 people by researchers at the University of Pittsburgh compared the children of people with bipolar disorder to those whose parents were unaffected. The children of parents with bipolar disorder were 13 times more likely to develop the problem themselves and 5 times more likely to develop another mood disorder. Children of two parents with bipolar disorder were 3.6 times more likely to have bipolar themselves than children with one parent with the condition.
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